List of possible malfunctions | Diagnostics | Elimination Methods |
The crankshaft does not rotate with the starter | ||
The battery is empty | The voltage at the battery terminals with the consumers turned off is below 12 V. When the starter is turned on, a crackling noise may be heard from under the hood | Charge the battery; if it doesn't charge, replace it |
Decreased battery capacity | The voltage at the battery terminals with the consumers turned off is more than 12 V, but when the starter is turned on, it drops below 6–8 V. At the same time, crackling may be heard from under the hood. Make sure there is no short in the starter (see below) | Charge the battery with low current (no more than 1 A); if its performance is not restored - replace |
Oxidized or loose battery terminals | When the starter is turned on, the voltage in the on-board network drops much more than at the battery terminals. When the starter is turned on, a crackling sound can be heard from under the hood | Crimp the terminals, clean the contacts, lubricate them with any grease |
Engine oil too thick | Check the oil on the dipstick: a drop should be liquid | Change the oil to suit the climate (see Used fuels, lubricants and operating fluids) |
Jammed engine or attachments | Check the free rotation of the crankshaft, generator, coolant pump. To do this, you can turn the crankshaft by the pulley nut with a special key, the crank by the ratchet (on those cars where there is a hole for it) or push the car by 1-2 people, including the highest gear | Repair the engine, generator, replace the coolant pump |
The starter traction relay control circuit is faulty: the wires are damaged, their tips are oxidized or loose, the contacts do not close «30» and «50» ignition switch or starter relay | When the key is turned to position «starter» traction relay does not work (no click under the hood). Check if 12 V is supplied to the control contact of the traction relay | Strip, crimp the tips of the wires; replace the faulty ignition switch or its contact part, the starter relay |
Short circuit or open circuit in the solenoid winding of the starter relay. Relay Armature Stuck (anchor misalignment, surface contamination, corrosion, etc.) | When the key is turned to position «starter» traction relay does not work (no click under the hood), but 12 V is supplied to the control contact of the traction relay. Remove the starter, relay, check its operation | Replace defective traction relay |
The contacts of the traction relay or wires are oxidized, poor contact «masses» | When the starter is turned on, a click is heard under the hood, but the starter armature does not rotate. Check circuit resistance with an ohmmeter «battery - starter», including wires «masses» (from body to clutch housing and from body to cylinder head). If the circuits are good, remove the starter and check its operation | Tighten the wire ends, crimp the terminals. Faulty traction relay (or starter) replace |
collector burning, brushes stuck or worn | Make sure the traction relay is working. You can supply power to the starter bypassing the relay. (Caution, avoid sparks near the battery!) On the removed starter, check the brush pressure to the commutator, their residual height, commutator wear | Clean the collector with fine-grained glass sandpaper, rinse with unleaded gasoline, ensure that the brushes move freely in the sockets. If the manifold is very worn, replace the starter |
Open or short in armature winding | Make sure the traction relay is working. You can supply power to the starter bypassing the relay. (Caution, avoid sparks near the battery!) The armature winding is checked after disassembling the starter with an ohmmeter or by darkening the insulation | Replace starter |
Open or short circuit in the holding winding of the starter relay | When the starter is turned on, a crack is heard from under the hood. The voltage on the battery and on the control contact of the traction relay is within normal limits. The relay is checked with an ohmmeter or by its excessive heating | Replace starter relay |
Freewheel slip | When the starter is turned on, the armature rotates, but the flywheel is stationary. First make sure that the traction relay is working properly and the drive gear engages with the flywheel crown (on the removed starter, the gear does not stick on the axle, the teeth of the flywheel crown are in good condition). | Replace clutch or starter. |
Damaged starter clutch gear or flywheel teeth | Inspection after disassembly | Replace crown or flywheel. You can repress the old flywheel crown by turning it over with the unworn side. |
The ring gear rotates on the flywheel | Screeching, howling from the clutch housing (when the starter is turned on, the ring gear rotates, the flywheel is stationary; the crankshaft can turn jerkily, with slipping) | Replace crown or flywheel |
Loud noise during starter operation | ||
The starter is skewed to the engine, its fastening is loose or the cover on the drive side is broken | Inspection | Tighten threaded connections to the specified torque, replace broken, worn parts or starter assembly |
Loose starter pole (anchor touches him) | Disassemble the starter, inspect, check the alignment of the poles and the gap between them and the anchor | Tighten the poles or replace the starter |
Excessive wear on bearing bushings or armature shaft journals | Inspection after disassembling the starter | Replace starter |
The ring gear rotates on the flywheel | When the starter is turned on, the ring gear rotates, the flywheel is stationary. Screeching, howling from the clutch housing | Replace flywheel ring |
Worn starter drive gear teeth or (more often) flywheel ring | Inspection | Replace starter or flywheel. You can repress the old flywheel crown by turning it over with the unworn side. |
The gear does not disengage from the flywheel: the drive lever jams; loose or broken freewheel or starter traction relay; the clutch on the splines of the armature shaft or the core of the traction relay sticks; faulty ignition switch (contacts do not open «30» and «50») or starter relay | Checking the removed starter, inspection after disassembly. The operation of the ignition switch can be checked with an ohmmeter or visually by removing its contact part | Replace starter traction relay or starter assembly; ignition switch contact group or switch assembly, starter enable relay |
The crankshaft is turned by a starter, but the engine is not started up | ||
There is no fuel in the tank | According to the indicator and control lamp of the fuel level | Fill up with fuel |
The battery is empty | The voltage at the battery terminals with consumers turned off is below 12 V. After a few revolutions, the starter stops turning the crankshaft, and a crackling noise may be heard from under the hood | Charge the battery; if it doesn't charge, replace it |
Reduced battery capacity | The voltage at the battery terminals with the consumers turned off is more than 12 V, but when the starter is turned on, it drops to 6–8 V. After a few revolutions, the starter stops turning the crankshaft, and crackling can be heard from under the hood. Make sure there is no short in the starter (see above) | Charge the battery with low current (no more than 1 A); if its performance is not restored - replace |
Oxidized or loose battery terminals | When the starter is turned on, the voltage in the on-board network drops much more than at the battery terminals. There may be a crackling noise coming from under the hood | Crimp the terminals, clean the contacts, lubricate them with any grease |
Malfunction in the low voltage circuit | Check with the ignition on whether voltage is applied to the ignition coil. Check with an ohmmeter the circuit from the ignition coil to the breaker contacts [K] or to the switch [B] | Strip oxidized tips, tighten loose wire fasteners, replace damaged wires, ignition switch or its contact part |
[K] The gap between the breaker contacts is not adjusted | Gap 0.35–0.45 mm is checked with a flat feeler gauge | Adjust gap |
[K] The contact group of the breaker-distributor is faulty: the contacts are damaged or oily, the spring is weakened, the movable contact sticks on the axis | Inspection, check by autotester (see Ignition system) | Clean worn contacts with a file (check their parallelism, no offset) and wipe dry. In case of weakening of the spring, jamming or severe wear of the contacts, replace the contact group |
[K] Faulty capacitor | Remove the central wire from the ignition distributor and fix its tip at a distance of 5–6 mm from «masses» car. With the ignition on, manually open the breaker contacts (slightly turning it by the slider). If between the wire and «weight» a strong, with a click, blue spark jumps - the capacitor is working. If the spark is weak, filiform or absent at all, close the contacts with a piece of wire or a screwdriver. Strengthening the spark in this case will indicate a malfunction of the capacitor | Replace defective capacitor |
[B] Faulty Hall sensor or its electrical circuits | Determined by a voltmeter (see Ignition system) or by replacing the sensor with a known good one | Replace defective sensor |
[B] Faulty switch | Substitute a known-good switch | Replace defective switch |
Damage to high-voltage devices and circuits | Having securely fixed the end of the high-voltage wire at a distance of 5-6 mm from «masses» car, crank the engine with a starter (do not touch high voltage circuits!). between wire and «weight» should spark regularly (Use only known-good high-voltage wires for testing). If there is no spark at the output of the ignition coil, the coil is faulty, if at the output or terminals of the ignition distributor, the slider or distributor cap is faulty. Burnouts of the slider or cover are determined visually. The health of the slider resistor is checked with an ohmmeter | Replace the defective coil, high-voltage wires, slider. Heavy Duty (salt on the roads, frost alternating with thaws) it is advisable to replace the wires every 5 years |
The high voltage wires are connected to the ignition distributor in the wrong order | Inspection | Connect the wires according to the firing order of the cylinders (1–3–4–2) |
The gap between the electrodes of the candles does not correspond to the norm | Gap 0.5–0.6 mm [K] (0.7–0.8 mm [B]) checked with a round probe | By bending the side electrode, set the desired gap or replace the candles |
Defective candles | Replace spark plugs with known good ones or check at a special stand [SRT]. The absence of external damage and sparking between the electrodes on an inverted candle does not allow us to conclude that it is working | Replace faulty spark plugs |
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
Valve timing broken | Check the alignment of the marks on the crankshaft and camshaft (see Engine) | Set the correct relative position of the shafts (by tags) |
12 V is not supplied to the idle solenoid valve or the valve itself is faulty | We check the supply voltage and the absence of a break in the valve winding with an autotester. The actuation of the valve can be determined by clicking | You can temporarily apply voltage to the valve directly from the terminal «» battery (preferably with a fuse) or, having unscrewed the defective valve, remove its plastic locking needle or replace the valve with a jet holder (in this case, after turning off the ignition, the engine may flash) |
Clogged fuel filters, frozen water in the power system, pinched hoses, deformed fuel line tubes | When cranking the engine with a starter, there is no smell of gasoline from the exhaust pipe. There is no gasoline in the carburetor float chamber - when you press «gas» there is no jet of fuel from the accelerator pump nozzle (visible when the air filter housing cover is removed). | In winter, roll the car into a warm garage, blow (tire pump) power supply system from the engine to the gas tank, replace defective hoses and tubes |
Fuel pump not working | Remove the fuel supply hose from the carburetor and, holding it with your finger, pump fuel with the pump lever. A serviceable pump must develop a noticeable pressure, which must be kept in the hose for at least 10 s. Check the correct installation of the fuel pump (protrusion of the pusher) (see Engine power system) | Replace the fuel pump or its diaphragms, adjust the protrusion of the pusher (installation gaskets), if necessary, replace the pusher |
Faulty or misadjusted carburetor starter or drive | See Carburetor | Adjust starter, replace worn parts |
Intake of foreign air into the intake manifold | Inspect the joints, check the fit of the hoses, fittings, tightness of the clamps. Temporarily disable the vacuum brake booster by pinching the appropriate hose (the effort on the brake pedal will increase significantly!) | Torn gaskets, parts with deformed flanges, defective vacuum booster Replace |
Clogged carburetor fuel jets (main fuel and idle) | The engine starts only after a few vigorous presses on the pedal «gas». A hot engine starts better than a cold one. | Wash with solvent or acetone and blow out the jets, if heavily soiled, clean them with a fishing line or a softwood needle. Screw jets tightly (do not damage the thread and jet!) |
The carburetor fuel jets are loose. Clogged air jets | A strong smell of gasoline is felt from the exhaust pipe, a cold engine starts better than a hot one. Fuel level in float chamber is normal (remove the carburetor cover to check) (see Carburetor) | Wash with solvent or acetone and blow out the jets, if heavily soiled, clean them with a fishing line or a softwood needle. Screw jets tightly (do not damage the thread and jet!) |
Excessive fuel level in the carburetor float chamber | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a warm one. Remove the carburetor cover, check the tightness of the float, the ease of its movement and the absence of touching the walls of the float chamber, the tightness of the needle valve. With the cap turned upside down, pump gasoline with the fuel pump manual priming lever. The slightest leak of gasoline from under the needle or valve seat is unacceptable | Replace needle valve, adjust float chamber fuel level (see Carburetor) |
Over-enriched mixture due to gasoline leaking into the engine crankcase through a torn fuel pump diaphragm | The oil on the dipstick smells like gasoline, the low oil pressure indicator may light up at idle | Replace the fuel pump or its diaphragms; if there is a lot of gasoline in the oil, then the oil |
In cold weather, the engine starts easily, but immediately stalls, and only after several attempts to start it starts to work stably | ||
out of order (the telescopic rod spring is weakened, the diaphragm is torn) or the carburetor starter is not adjusted | Checking the performance of the starting device: short the wire from the ignition coil to «mass», remove the air filter housing cover, fully close the choke and crank the engine with the starter (ask an assistant) - the damper should not open slightly. Insert the high voltage wire into the distributor and ask to start the engine (it must be cold) – as soon as the engine starts, the damper should open by 5 mm (see Carburetor) | Replace the diaphragm, telescopic rod or choose a stiffer spring (see Carburetor) |
Engine starts for a long time | ||
Evaporated gasoline from the float chamber of the carburetor (after a long stay, especially in hot weather) | — | After a long period of parking, you can pump up gasoline with the fuel pump manual priming lever |
Engine runs erratically or stalls at idle | ||
Engine is not warm | By temperature gauge | Warm up the engine to operating temperature |
Clogged fuel lines, fuel filters, water in fuel | Inspection, replacement | Clean the fuel inlet mesh, fuel filters, if low quality gasoline is suspected, especially on the eve of the winter season, use special fuel additives that bind water. After using them, it is recommended to wash or replace the fuel filters |
Engine idle adjustment is broken | See Carburetor | Adjust idle (see Carburetor) |
Intake of foreign air into the intake manifold | Inspect the joints, check the fit of the hoses, fittings, tightness of the clamps. Temporarily disable the vacuum brake booster by pinching the appropriate hose (the effort on the brake pedal will increase significantly!) | Torn gaskets, parts with deformed flanges, defective vacuum booster Replace |
Clogged carburetor fuel jets (main fuel and idle) | The engine starts only after a few vigorous presses on the pedal «gas». A hot engine starts better than a cold one. | Rinse with gasoline or acetone and blow through the jets, if heavily soiled, clean them with a fishing line or softwood needle. Screw jets tightly (Not damage the thread and jet!) |
Insufficient fuel level in the carburetor float chamber | The engine starts badly and «pulls». Possible pops in the carburetor. When pulling the button «suction» jerks and dips decrease or disappear completely. Remove the carburetor cap to check the fuel level (see Carburetor) | Adjust fuel level (see Carburetor) |
The fuel pump does not create the necessary pressure in the system | Remove the fuel supply hose from the carburetor and, holding it with your finger, pump fuel with the pump lever. A serviceable pump must develop a noticeable pressure, which must be kept in the hose for at least 10 s. Check the correct installation of the fuel pump (protrusion of the pusher) (see Engine power system) | Replace the fuel pump or its diaphragms, adjust the protrusion of the pusher (installation gaskets), if necessary, replace the pusher |
The carburetor fuel jets are loose. Clogged air jets | A strong smell of gasoline is felt from the exhaust pipe, a cold engine starts better than a hot one. Fuel level in float chamber is normal (remove the carburetor cover to check) (see Carburetor) | Rinse with gasoline or acetone and blow through the jets, if heavily soiled, clean them with a fishing line or softwood needle. Screw jets tightly (do not damage the thread and jet!) |
Excessive fuel level in the carburetor float chamber | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a hot one. Remove the top cover of the carburetor, check the tightness of the float, its ease of movement and the absence of touching the walls of the float chamber. Checking the tightness of the needle valve: after removing the carburetor cap and turning it upside down, pump gasoline with the fuel pump lever. The slightest leak of gasoline from under the needle or valve seat is unacceptable | Replace needle valve, adjust float chamber fuel level (see Carburetor) |
Re-enrichment of the mixture due to leakage of gasoline into the engine crankcase through a torn fuel pump diaphragm | The oil on the dipstick smells like gasoline, the low oil pressure indicator may light up at idle | Replace the fuel pump or its diaphragms; if there is a lot of gasoline in the oil, then the oil |
12 V is not supplied to the idle solenoid valve or the valve itself is faulty | We check the supply voltage and the absence of a break in the valve winding with an autotester. The actuation of the valve can be determined by clicking | You can temporarily apply voltage to the valve directly from the terminal «» battery (preferably with a fuse) or, having unscrewed the defective valve, remove its plastic locking needle or replace the valve with a jet holder (in this case, after turning off the ignition, the engine may flash) |
The gap between the electrodes of the candles does not correspond to the norm | The gap between the electrodes of the candles does not correspond to the norm | By bending the side electrode, set the desired gap or replace the candles |
Strong soot on the electrodes of the spark plugs; ingress of soot particles into the gap between the electrodes | Inspection | Clean spark plugs with compressed air or mechanically (do not damage the insulator!), make sure they work [SRT] (the absence of external damage and sparking between the electrodes on an inverted candle does not allow us to conclude that it is working). Identify and eliminate the cause of increased carbon formation in the combustion chamber, replace the spark plugs if necessary |
Defective spark plugs: leakage current through cracks in the insulator or carbon deposits on the thermal cone, poor contact in the center electrode assembly | Replace spark plugs with known good ones or check at a special stand [SRT]. The absence of external damage and sparking between the electrodes on an inverted candle does not allow us to conclude that it is working | Replace faulty spark plugs |
Damage to high-voltage devices and circuits | Having securely fixed the end of the high-voltage wire at a distance of 5-6 mm from «masses» car, crank the engine with a starter (do not touch high voltage circuits!). between wire and «weight» should spark regularly (Use only known-good I/O wires for testing). If there is no spark at the output of the ignition coil, the coil is faulty, if at the output / outputs of the ignition distributor, the slider or distributor cap is faulty. Burnouts of the slider or cover are determined visually. The health of the slider resistor is checked with an ohmmeter | Replace the defective coil, high-voltage wires, slider. Heavy Duty (salt on the roads, frost alternating with thaws) it is advisable to replace the wires every 5 years |
Wear, damage, weakening of the coal spring in the distributor cap | Inspection with cover removed | Replace distributor cap or ember with spring |
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
Poor contact in the low voltage circuit | Check with the ignition on whether voltage is applied to the ignition coil. Check with an ohmmeter the circuit from the ignition coil to the breaker contacts [K] or to the switch [B] | Strip oxidized tips, tighten loose wire fasteners, replace damaged wires, ignition switch or its contact part |
[K] The contact group of the breaker-distributor is faulty: the contacts are damaged or oily, the spring is weakened, the movable contact sticks on the axis | Inspection, check by autotester (see Ignition system) | Clean worn contacts with a file (check their parallelism, no offset) and wipe dry. In case of weakening of the spring, jamming or severe wear of the contacts, replace the contact group |
[B] Faulty Hall sensor or its electrical circuits | Determined by a voltmeter (see Ignition system) or by replacing the sensor with a known good one | Replace defective sensor |
[B] Faulty switch | Substitute a known-good switch | Replace the failed switch |
[K] Decrease in capacitance of the capacitor or poor contact in its circuit | Check the circuit with an autotester. To check the capacitor, remove the central wire from the ignition distributor and fix its tip at a distance of 5–6 mm from «masses» car. With the ignition on, manually open the breaker contacts (slightly turning it by the slider). If between the wire and «weight» a strong, with a click, blue spark jumps - the capacitor is working. If the spark is weak, filiform or absent at all, close the contacts with a piece of wire or a screwdriver. Strengthening the spark in this case will indicate a malfunction of the capacitor | If you suspect a defective capacitor, replace it |
Weakening or breakage of the springs of the weights of the centrifugal regulator of the ignition distributor, the damper rings of the weights are lost, jamming of the weights | Visually and on a special stand [STO] | Replace ignition distributor |
Fuzzy operation of the vacuum ignition timing controller: when the vacuum is removed, the plate does not return to its original position, there is a large play in the bearing | Inspection. The characteristic of the vacuum regulator is taken on a special stand [STO] | Eliminate jamming, replace faulty vacuum regulator or ignition distributor assembly |
Valve timing broken | Check the alignment of the marks on the crankshaft and camshaft (see Engine) | Set the correct relative position of the shafts (by tags) |
Valve clearance not adjusted | Checked with a set of probes (see Engine) | Adjust gaps |
Strong wear of the camshaft cams | Inspection after partial disassembly of the engine | Replace camshaft |
Low compression in the cylinders (less than 10 kgf/cm2) or its greater unevenness in the cylinders (more than 2 kgf/cm2): Worn or damaged valves, seats, worn, stuck or broken piston rings | Warm up the engine to operating temperature and remove the spark plugs. Fully press the pedal «gas» and, inserting a compression gauge into the spark plug holes, turn the crankshaft with a starter (work together). At the same time, you should close «mass» high voltage wire of the ignition coil. Repeat the measurements, pouring into the cylinders through the spark plug holes 10–15 cm3 engine oil. In those cylinders where the compression has increased by more than 2 kgf / cm2, possibly badly worn, broken or stuck rings. If the compression remains below 10 kgf/cm2, the valves or their seats may be worn or damaged | Replace rings, pistons. Repair the cylinder block [SRT]. Lap the valves to the seats, if necessary, replace the valves, their guide bushings, grind the seats [STO] |
Low idle | ||
Idle adjustment broken engine stroke | See Carburetor | Adjust idle |
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
Engine is not warm | By temperature gauge | Warm up the engine to operating temperature |
Stranger suction air into intake manifold | Inspect the joints, check the fit of the hoses, fittings, tightness of the clamps. Temporarily disable the vacuum brake booster by pinching the appropriate hose (the effort on the brake pedal will increase significantly!) | Torn gaskets, parts with deformed flanges, defective vacuum booster Replace |
Clogged carburetor fuel jets (main fuel and idle) | The engine starts only after a few vigorous presses on the pedal «gas». A hot engine starts better than a cold one. | Rinse with gasoline or acetone and blow through the jets, if heavily soiled, clean them with a fishing line or softwood needle. Screw jets tightly (do not damage the thread and jet!) |
Insufficient fuel level in the carburetor float chamber | The engine starts badly and «pulls». Possible pops in the carburetor. When pulling the button «suction» jerks and dips decrease or disappear completely. Remove the carburetor cap to check the fuel level (see Carburetor) | Adjust fuel level (see Carburetor) |
Excessive fuel level in the carburetor float chamber | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a hot one. Remove the top cover of the carburetor, check the tightness of the float, its ease of movement and the absence of touching the walls of the float chamber. Checking the tightness of the needle valve: after removing the carburetor cap and turning it upside down, pump gasoline with the fuel pump lever. The slightest leak of gasoline from under the needle or valve seat is unacceptable | Replace leaky needle valve, adjust float chamber fuel level (see Carburetor) |
The carburetor fuel jets are loose. Clogged air jets | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a hot one. Fuel level in float chamber is normal (remove the carburetor cover to check) (see Carburetor) | Rinse with gasoline or acetone and blow through the jets, if heavily soiled, clean them with a fishing line or softwood needle. Screw jets tightly (do not damage the thread and jet!) |
Increased resistance to air flow in the intake tract | Check air cleaner element, intake tract (absence of foreign objects, leaves, etc.) | Clean the intake tract, replace the dirty air filter element |
High idle | ||
Engine idle adjustment is broken | See Carburetor | Adjust idle |
Long driving at high engine speeds | After 30–40 s of idling, the revolutions decrease to normal | Not a malfunction |
Throttle Actuator Malfunction (pedals «gas»), weakened return spring on the carburetor | Check pedal travel, drive clearance (pedal free play), make sure there are no jammed parts | Replace defective parts, lubricate the cable with engine oil |
Faulty or out of adjustment carburetor starter or drive | See Carburetor | Adjust starter, replace worn parts |
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
Excessive fuel level in the carburetor float chamber | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a hot one. Remove the top cover of the carburetor, check the tightness of the float, its ease of movement and the absence of touching the walls of the float chamber. Checking the tightness of the needle valve: after removing the carburetor cap and turning it upside down, pump gasoline with the fuel pump lever. The slightest leak of gasoline from under the needle or valve seat is unacceptable | Replace leaky needle valve, adjust float chamber fuel level |
Clogged idle air jet | Inspection after disassembly | Rinse with unleaded gasoline or acetone and blow through the jet. If heavily soiled, clean it with a fishing line or soft wood needle. Flush the crankcase ventilation system |
Over-enriched mixture due to gasoline leaking into the engine crankcase through a torn fuel pump diaphragm | The oil on the dipstick smells like gasoline, the low oil pressure indicator may light up at idle | Replace the fuel pump or its diaphragms; if there is a lot of gasoline in the oil, then the oil |
Carburetor throttles not fully closing | The gap between the throttle valve and the walls of the mixing chamber is visible through the light | Use the stop screws on the shutters to close them completely. In this case, the dampers should open easily, without jamming. After adjusting the screws fill with paint |
The carburetor dampers are mounted on skewed axles and do not close at any position of the stop screws | Inspection | Leaning the damper axles on a suitable stop (not to bend them), loosen the screws and, after correctly orienting the shutters, tighten them [HUNDRED] (or replace the carburetor or throttle body) |
Ingress of foreign objects under the throttle valve or its actuator | Inspection | Remove foreign object, check damper operation |
In cold weather, the engine stalls shortly after the start of movement, but after a short stop it starts again | ||
An ice plug has formed in the carburetor diffuser (heated air hose is not connected to the outlet on the exhaust manifold) | Inspection | Secure the hose to the heated air intake with a hose clamp. |
In hot weather, the engine spontaneously stops | ||
Steam lock in the power system | Inspect the fuel lines, blow out the line with a tire pump | Eliminate kinks in hoses, replace deformed tubes |
The engine does not develop full power and does not have sufficient throttle response. Jerks and dips when driving a car | ||
Engine is not warm | By temperature gauge | Warm up the engine to operating temperature |
There is little fuel in the tank | According to the indicator and control lamp of the fuel level | Top up fuel |
The fuel pump does not create the necessary pressure in the system | Remove the fuel supply hose from the carburetor and, holding it with your finger, pump fuel with the pump lever. A serviceable pump must develop a noticeable pressure, which must be kept in the hose for at least 10 s. Check the correct installation of the fuel pump (protrusion of the pusher) (see Engine power system) | Replace the fuel pump or its diaphragms, adjust the protrusion of the pusher (installation gaskets), if necessary, replace the pusher |
Clogged fuel lines, fuel filters, pinched hoses, deformed tubes, water in fuel | Inspection | Clean the mesh of the gas receiver, wash or replace the filters, defective tubes, eliminate the kinks in the hoses. In winter, roll the car into a warm garage, blow (tire pump) power supply system from the engine to the gas tank. If low quality gasoline is suspected, especially on the eve of the winter season, use special fuel additives that bind water. After using them, it is recommended to wash or replace the fuel filters |
Insufficient fuel level in the carburetor float chamber | Insufficient fuel level in the carburetor float chamber | Adjust fuel level (see Engine power system) |
Clogged jets and carburetor channels. Jets not tightly wrapped | Inspect, blow channels and jets | Rinse with gasoline or acetone and blow through the jets, if heavily soiled, clean them with a fishing line or softwood needle. Screw jets tightly (do not damage the thread and jet!) |
The diaphragm of the accelerator pump is torn, its lever is jammed, the atomizer or supply channels are clogged | Check the pump flow, the direction of the jet, the absence of gasoline leakage from under the diaphragm. Make sure that the accelerator pump lever moves freely | Replace damaged parts, tighten threaded connections, purge valves |
Intake of foreign air into the intake manifold | Inspect the joints, check the fit of the hoses, fittings, tightness of the clamps. Disconnect the vacuum brake booster for a short time by pinching the corresponding hose (Caution: the effort on the brake pedal will increase significantly!) | Torn gaskets, parts with deformed flanges, defective vacuum booster Replace |
Excessive fuel level in the carburetor float chamber | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a hot one. Remove the top cover of the carburetor, check the tightness of the float, its ease of movement and the absence of touching the walls of the float chamber. Checking the tightness of the needle valve: after removing the carburetor cap and turning it upside down, pump gasoline with the fuel pump lever. The slightest leak of gasoline from under the needle or valve seat is unacceptable (see Carburetor) | Replace needle valve, adjust float chamber fuel level |
Over-enriched mixture due to gasoline leaking into the engine crankcase through a torn fuel pump diaphragm | The oil on the dipstick smells like gasoline, the low oil pressure indicator may light up at idle speed, idling is unstable | Replace the fuel pump or its diaphragms; if there is a lot of gasoline in the oil, then the oil |
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
Malfunction in the low voltage circuit | Check with the ignition on whether voltage is applied to the ignition coil. Check with an ohmmeter the circuit from the ignition coil to the breaker contacts [K] or to the switch [B] | Strip oxidized tips, tighten loose wire fasteners, replace damaged wires, ignition switch or its contact part |
[B] Faulty Hall sensor or its electrical circuits | Determined by a voltmeter (see Ignition system) or by replacing the sensor with a known good one | Replace defective sensor |
[B] Faulty switch | Substitute a known-good switch | Substitute a known-good switch |
[K] The contact group of the distributor breaker is faulty: the contacts are damaged or oily, the spring is weakened, the movable contact sticks on the axis | Inspection, check by autotester (see Ignition system) | Clean worn contacts with a file (check their parallelism, no offset) and wipe dry. In case of weakening of the spring, jamming or severe wear of the contacts, replace the contact group |
[K] Decrease in capacitance of the capacitor or poor contact in its circuit | Check the circuit with an autotester. To check the capacitor, remove the central wire from the ignition distributor and fix its tip at a distance of 5–6 mm from «masses» car. With the ignition on, manually open the breaker contacts (slightly turning it by the slider). If between the wire and «weight» a strong, with a click, blue spark jumps - the capacitor is working. If the spark is weak, filiform or absent at all, close the contacts with a piece of wire or a screwdriver. Strengthening the spark in this case will indicate a malfunction of the capacitor | If you suspect a defective capacitor, replace it |
Weakening or breakage of the springs of the weights of the centrifugal regulator of the ignition distributor, the damper rings of the weights are lost, jamming of the weights | Visually and on a special stand [STO] | Replace ignition distributor |
Fuzzy operation of the vacuum ignition timing controller: when the vacuum is removed, the plate does not return to its original position, there is a large play in the bearing | Inspection. The characteristic of the vacuum regulator is taken on a special stand [STO] | Eliminate jamming, replace faulty vacuum regulator or ignition distributor assembly |
The gap between the electrodes of the candles does not correspond to the norm | Gap 0.5–0.6 mm [K] (0.7–0.8 mm [B]) checked with a round probe | By bending the side electrode, set the desired gap or replace the candles |
Strong soot on the electrodes of the spark plugs; ingress of soot particles into the gap between the electrodes | Inspection | Clean spark plugs with compressed air or mechanically (do not damage the insulator!), make sure they work [SRT] (the absence of external damage and sparking between the electrodes on an inverted candle does not allow us to conclude that it is working). Identify and eliminate the cause of increased carbon formation in the combustion chamber, replace the spark plugs if necessary |
Defective spark plugs: leakage current through cracks in the insulator or carbon deposits on the thermal cone, poor contact in the center electrode assembly | Replace spark plugs with known good ones or check at a special stand [SRT]. (The absence of external damage and sparking between the electrodes on an inverted candle does not allow us to conclude that it is working.) | Replace faulty spark plugs |
Wear, damage to the contact carbon in the cover of the ignition distributor. Coal spring weakened | Inspection | Replace distributor cap or ember with spring |
Insulation burnout of high-voltage circuits | Checked with an ohmmeter and visually (black cracks, insulation melting). To test high-voltage wires, replace them with known good ones | Replace faulty ignition distributor cap, runner, ignition coil, high voltage wires |
Incomplete throttle opening | Determined visually on a stopped engine | Adjust throttle actuator |
Valve timing broken | Check the alignment of the marks on the crankshaft and camshaft (see Engine) | Set the correct relative position of the shafts (by tags) |
Low compression in the cylinders (less than 10 kgf/cm2) or its greater unevenness in the cylinders (more than 2 kgf/cm2): Worn or damaged valves, seats, worn, stuck or broken piston rings | Warm up the engine to operating temperature and remove the spark plugs. Fully press the pedal «gas» and, inserting a compression gauge into the spark plug holes, turn the crankshaft with a starter (work (more than 2 kgf/cm2): Worn or damaged valves, seats, worn, stuck or broken piston rings | Replace rings, pistons. Repair the cylinder block [SRT]. Lap the valves to the seats, if necessary, replace the valves, their guide bushings, grind the seats |
Valve clearance not adjusted | Checked with a set of probes (See Engine) | Adjust gaps |
Strong wear of the camshaft cams | Inspection after partial disassembly of the engine | Replace worn camshaft |
Sediment or broken valve springs | Inspection, measurement of the length of springs in a free state and under load (after partial disassembly of the engine) | Replace weak or broken springs |
Pops in the intake manifold | ||
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
Valve timing broken | Check the alignment of the marks on the crankshaft and camshaft (see Engine) | Set the correct relative position of the shafts (by tags) |
Shots in the silencer | ||
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
[K] Faulty capacitor | Remove the central wire from the ignition distributor and fix its tip at a distance of 5–6 mm from «masses» car. With the ignition on, manually open the breaker contacts (slightly turning it by the slider). If between the wire and «weight» a strong, with a click, blue spark jumps - the capacitor is working. If the spark is weak, filiform or absent at all, close the contacts with a piece of wire or a screwdriver. Strengthening the spark in this case will indicate a malfunction of the capacitor | Replace defective capacitor |
[B] Faulty switch | Substitute a known-good switch | Replace defective switch |
Valve timing broken | Check the alignment of the marks on the crankshaft and camshaft (see Engine) | Set the correct relative position of the shafts (by tags) |
Insulation burnout of high-voltage circuits | Checked with an ohmmeter and visually (black cracks, insulation melting). Replace high-voltage wires for testing with known good ones | Replace faulty ignition distributor cap, slider, high voltage wires |
Faulty ignition coil | Substitute a known-good coil to test | Replace defective coil |
Claps in the intake manifold after the engine is running at power levels | ||
Candles with the wrong glow rating are used | — | Use spark plugs recommended by the manufacturer |
Increased fuel consumption | ||
Leakage of the power system | Smell of gasoline | Tighten hose clamps, threaded connections. Check fit of fittings; if the fit is loose, replace the relevant components |
Over-enriched mixture due to gasoline leaking into the engine crankcase through a torn fuel pump diaphragm | The oil on the dipstick smells like gasoline, the low oil pressure indicator may light up at idle | Replace the fuel pump or its diaphragms; if there is a lot of gasoline in the oil, then the oil |
Increased resistance to vehicle movement | Warm car run (after running at least 20 km) from a speed of 50 km / h must be at least 500 m | Check and adjust tire pressure, front wheel alignment, brake system |
Faulty or misadjusted carburetor starter or drive | See Carburetor | Adjust starter, replace worn parts |
Excessive fuel level in the carburetor float chamber | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a hot one. Remove the top cover of the carburetor, check the tightness of the float, its ease of movement and the absence of touching the walls of the float chamber. Checking the tightness of the needle valve: after removing the carburetor cap and turning it upside down, pump gasoline with the fuel pump lever. The slightest leak of gasoline from under the needle or valve seat is unacceptable (see Carburetor) | Replace needle valve, adjust float chamber fuel level |
The carburetor fuel jets are loose. Air jets clogged. Accelerator pump valve leaking | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a hot one. Fuel level in float chamber is normal (remove the carburetor cover to check) (see Carburetor) | Rinse with gasoline or acetone and blow through the jets, if heavily soiled, clean them with a fishing line or softwood needle. Screw jets tightly (do not damage the thread and jet!) |
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
[K] Ignition misfires: the contact group of the breaker-distributor is faulty: the contacts are damaged or oily, the spring is weakened, the movable contact sticks on the axis | Inspection, check by autotester (see Ignition system) | Clean worn contacts with a file (check their parallelism, no offset) and wipe dry. In case of weakening of the spring, jamming or severe wear of the contacts, replace the contact group |
[K] Misfiring: a decrease in the capacitance of the capacitor or poor contact in its circuit | Check the circuit with an autotester. To check the capacitor, remove the central wire from the ignition distributor and fix its tip at a distance of 5–6 mm from «masses» car. With the ignition on, manually open the breaker contacts (slightly turning it by the slider). If between the wire and «weight» a strong, with a click, blue spark jumps - the capacitor is working. If the spark is weak, filiform or absent at all, close the contacts with a piece of wire or a screwdriver. Strengthening the spark in this case will indicate a malfunction of the capacitor | If you suspect a defective capacitor, replace it |
[B] Faulty switch | Substitute a known-good switch | Replace defective switch |
Weakening or breakage of the springs of the weights of the centrifugal regulator of the ignition distributor, the damper rings of the weights are lost, jamming of the weights | Visually and on a special stand [STO] | Replace ignition distributor |
Fuzzy operation of the vacuum ignition timing regulator: when the vacuum is removed, the plate does not return to its original position | Inspection. The characteristic of the vacuum regulator is taken on a special stand [STO] | Eliminate jamming, replace faulty vacuum regulator or ignition distributor assembly |
Defective spark plugs: leakage current through cracks in the insulator or carbon deposits on the thermal cone, poor contact in the center electrode assembly | Replace spark plugs with known good ones or check at a special stand [SRT]. The absence of external damage and sparking between the electrodes on an inverted candle does not allow us to conclude that it is working. | Replace faulty spark plugs |
Engine idle adjustment is broken | See Carburetor | Adjust idle |
Carburetor throttles not fully closing | The gap between the throttle valve and the walls of the mixing chamber is visible through the light | Use the stop screws on the shutters to close them completely. In this case, the dampers should open easily, without jamming. After adjusting the screws fill with paint |
The carburetor dampers are mounted on skewed axles and do not close at any position of the stop screws | Inspection after removal of the carburetor | Leaning the damper axles on a suitable stop (not to bend them), loosen the screws and, after correctly orienting the shutters, tighten them [HUNDRED] (or replace the carburetor) |
Ingress of foreign objects under the throttle valve or its actuator | Inspection after removal of the carburetor | Remove foreign object, check damper operation |
Low compression in the cylinders (less than 10 kgf/cm2) or its greater unevenness in the cylinders (more than 2 kgf/cm2): Worn or damaged valves, seats, worn, stuck or broken piston rings | Warm up the engine to operating temperature and remove the spark plugs. Fully depress the pedal «gas» and, inserting a compression gauge into the spark plug holes, turn the crankshaft with a starter (work together). At the same time, you should close «mass» high voltage wire of the ignition coil. Repeat the measurements, pouring into the cylinders through the spark plug holes 10–15 cm3 engine oil. In those cylinders where the compression has increased by more than 2 kgf / cm2, possibly badly worn, broken or stuck rings. If the compression remains below 10 kgf/cm2, the valves or their seats may be worn or damaged | Replace rings, pistons. Repair the cylinder block [SRT]. Lap the valves to the seats, if necessary, replace the valves, their guide bushings, grind the seats |
Increased oil consumption (more than 1 liter per 1000 kilometers) | ||
Oil leakage through gaskets and cuffs: wear of sealing edges, hardening of gaskets, warping of mating surfaces | Wash the engine, then after a short run inspect for possible leaks | Tighten the screws securing the oil pan, timing cover, fuel pump; replace worn cuffs |
Oil leakage through gaskets and cuffs: the crankcase ventilation system is clogged | Inspection | Clean the ventilation system |
Wear, loss of elasticity of valve stem seals. Wear of valve stems, guide bushings | Parts Inspection | Replace worn parts |
Wear, breakage or coking (loss of mobility) piston rings. Wear of pistons, cylinders | Inspection after engine disassembly. see also «Low compression in cylinders...» | Replace rings, clean grooves in pistons. Replace worn pistons, bore and honing cylinders[STO] |
Insufficient oil pressure | ||
Little oil in the engine | By dipstick oil level | Add oil |
Use of oil of the wrong viscosity | — | Change oil |
Clogging of the oil receiver mesh | Inspection after removal of the oil pan | clear the grid |
Misalignment, clogging of the pressure reducing valve or weakening of its spring | Inspection after removal of the oil pan | Clean valve. Replace defective valve and/or spring |
Oil pump gear wear | Inspection (see Engine) | Replace worn gears |
Excessive clearance between bearings and crankshaft journals | Determined by measuring parts after disassembling the engine | Replace worn liners. If necessary, replace or repair [SRT]crankshaft |
Oil dilution due to gasoline leaking into the engine crankcase through a torn fuel pump diaphragm | The oil on the dipstick smells like gasoline, the low oil pressure indicator may light up at idle | Replace the fuel pump or its diaphragms; if there is a lot of gasoline in the oil, then the oil |
Faulty oil pressure sensor or pointer | Checking with a manometer and an ohmmeter (see control devices) | Replace faulty sensor or pointer |
The engine gets very hot (the coolant temperature gauge needle is in the red zone) | ||
Faulty temperature sensor or gauge | Check the pointer and sensor with an autotester (see control devices) | Faulty sensor, pointer replace |
Faulty thermostat | See Thermostat check | Replace defective thermostat |
The coolant pump drive belt is loose, the pulleys are oiled | Inspection (see Replacing the alternator drive belt) | Tighten the belt, replace if necessary. Eliminate the cause of oiling |
Faulty coolant pump | The pump pulley should turn easily by hand and have no play | Replace pump |
Too little fluid in the cooling system | The fluid level is below the mark on the expansion tank | Eliminate leaks. Add coolant (see «Coolant level drop in expansion tank») |
A lot of scale in the cooling system | — | Flush the cooling system with a descaling agent. Dilute concentrated antifreeze only with distilled water |
Radiator cells dirty | Inspection | Flush the radiator with a high pressure water jet |
Cooling fan does not turn on | Close the contacts of the radiator thermal switch between each other. If the fan is running (take care of your hands!) - the thermal switch is faulty, if not - the electrical circuits, relay or fan motor. Check if 12 V is being supplied to the control and power contacts of the electric fan relay. If yes, then the relay or fan motor is faulty, otherwise the relay power circuit (checked with an ohmmeter) | Restore contact in electrical circuits. Faulty thermal switch, relay, electric motor replace |
Unacceptably low octane number of gasoline | Engine operation is accompanied by distinct detonation knocks | Fill your car with fuel recommended by the manufacturer |
A lot of carbon deposits in the combustion chamber, on the bottoms of the pistons, valve plates | Inspection after removal of the cylinder head | Eliminate the cause of soot formation. (see «Increased fuel consumption», «Increased oil consumption»). Use oils of the recommended viscosity and, if possible, of high quality |
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
The electric fan of the engine cooling system is constantly running (even on a cold engine) | ||
Radiator thermal switch contacts not opening | If the fan stops working when the wire is disconnected from the thermal switch, the switch is faulty | Replace thermal switch |
The contacts of the relay for turning on the electric fan do not open | Check by tester | Replace relay |
The engine takes a long time to warm up to operating temperature | ||
Faulty thermostat | See Thermostat check | Replace defective thermostat |
Low air temperature (below -15°С) | — | Insulate the engine: install thermal and sound insulation of the hood, shields in front of the radiator (do not block the entire area of the radiator in the area of the fan impeller!) |
The electric fan of the engine cooling system is constantly running | Cm. «The electric fan of the engine cooling system is constantly running (even on a cold engine)» | |
Coolant level drop in expansion tank | ||
Damage to the radiator, hoses, loosening of their fit on the nozzles. Fluid leaking from heater tap | Inspection. Sealing of radiators (engine and heater) tested in a hot water bath with compressed air at a pressure of 1 kgf/cm2 | Replace damaged parts. Tighten hose clamps |
Fluid leaking through coolant pump cuff | Inspection | Replace pump |
Evaporation of liquid from the cooling system due to leakage of the radiator cap valves | With the engine stopped, squeeze the cooling system hoses with your hands. Liquid must not flow into the expansion tank (level should not increase) | Replace cap |
Cylinder head gasket damaged. Block or cylinder head defect | When changing the oil, an emulsion with a whitish tint is poured out of the crankcase. There may be copious white smoke from the muffler and oil stains on the fluid surface (in the expansion tank). Coolant leaks on the outer surface of the engine | Replace damaged parts. Check the flatness of the mating surfaces of the cylinder block and head |
Detonation (high-pitched metallic knocks, which usually occur when the engine is under load, especially at low speeds - acceleration «tightness» and so on. - and disappearing when the load is reduced) | ||
Unacceptably low octane number of gasoline | — | Fill your car with fuel recommended by the manufacturer |
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
Engine overheating | By temperature gauge | Eliminate the cause of overheating (see «The engine gets very hot») |
A lot of carbon deposits in the combustion chamber, on the bottoms of the pistons, valve plates | Inspection after removal of the cylinder head | Eliminate the cause of soot formation (see «Increased fuel consumption», «Increased oil consumption»). Use oils of the recommended viscosity and, if possible, of high quality |
Candles with the wrong glow rating are used | — | Use spark plugs recommended by the manufacturer |
Extraneous noises and knocks in the engine (except detonation, see above) | ||
Increased valve clearances | Clatter in the area of the cylinder head. Measure gaps with a feeler gauge | Adjust gaps |
Noise of the timing chain: its tension is not adjusted, the tensioner and / or damper is broken | Uniform noise at the front of the engine. It increases at medium speeds and variable loads (well heard when reset «gas» from 2000–2500 min–1 up to 1000–1500 min–1) | Pull the chain (see Engine). If necessary, replace the chain, tensioner, damper |
Broken valve spring | Uneven weak tapping in the cylinder head area. Inspection after partial disassembly of the engine | Replace spring |
Increased clearance between valve stem and guide sleeve | A knock of medium strength and height in the area of the cylinder head. The play is felt when swaying in the sleeve of a freely inserted (cracked) valve | Replace valve bushing |
Badly worn camshaft lobes (cutting) | The knock is the same as with increased clearances in the valve mechanism (see above), but the gap adjustment is not eliminated. Inspection after partial disassembly of the engine | Replace worn parts |
Knock crankshaft and camshaft, connecting rod bearings, pistons, piston pins, play or seizing in the bearings of the coolant pump | Service station check | Repair of parts at service stations or replacement of components and assemblies |
Severe engine vibration See also «Engine runs erratically or stalls at idle» | ||
Lost elasticity or collapsed power unit supports | Inspection | Replace supports |
Increased content of harmful substances in exhaust gases | ||
Excessive fuel level in the carburetor float chamber | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a hot one. Remove the top cover of the carburetor, check the tightness of the float, its ease of movement and the absence of touching the walls of the float chamber. Checking the tightness of the needle valve: after removing the carburetor cap and turning it upside down, pump gasoline with the fuel pump lever. The slightest leak of gasoline from under the needle or valve seat is unacceptable (see Carburetor) | Replace needle valve, adjust float chamber fuel level |
Over-enriched mixture due to gasoline leaking into the engine crankcase through a torn fuel pump diaphragm | The oil on the dipstick smells like gasoline, the low oil pressure warning light may come on at idle | Replace the fuel pump or its diaphragms; if there is a lot of gasoline in the oil, then the oil |
The starter or its drive is faulty or not adjusted | See Carburetor | Adjust starter, replace worn parts |
Engine idle adjustment is broken | See Carburetor | Adjust idle |
The carburetor fuel jets are loose. Air jets clogged. Accelerator pump valve leaking | There is a strong smell of gasoline from the exhaust pipe, a cold engine starts better than a hot one. Fuel level in float chamber is normal (remove the carburetor cover to check) (see Carburetor) | Rinse with gasoline or acetone and blow through the jets, if heavily soiled, clean them with a fishing line or softwood needle. Screw jets tightly (do not damage the thread and jet!) |
Incorrect ignition timing | See Ignition system | Adjust ignition timing |
[K] Ignition misfires: the contact group of the breaker-distributor is faulty: the contacts are damaged or oily, the spring is weakened, the movable contact sticks on the axis | Inspection, check by autotester (see Ignition system) | Clean worn contacts with a file (check their parallelism, no offset) and wipe dry. In case of weakening of the spring, jamming or severe wear of the contacts, replace the contact group |
[K] Misfiring: a decrease in the capacitance of the capacitor or poor contact in its circuit | Check the circuit with an autotester. To check the capacitor, remove the central wire from the ignition distributor and fix its tip at a distance of 5–6 mm from «masses» car. With the ignition on, manually open the breaker contacts (slightly turning it by the slider). If between the wire and «weight» a strong, with a click, blue spark jumps - the capacitor is working. If the spark is weak, filiform or absent at all, close the contacts with a piece of wire or a screwdriver. Strengthening the spark in this case will indicate a malfunction of the capacitor | If you suspect a defective capacitor, replace it |
[B] Faulty switch | Substitute a known-good switch | Replace the failed switch |
Insulation burnout of high-voltage circuits | Checked with an ohmmeter and visually (black cracks, insulation melting). To test high-voltage wires, replace them with known good ones | Replace faulty ignition distributor cap, runner, ignition coil, high voltage wires |
Defective spark plugs: leakage current through cracks in the insulator or carbon deposits on the thermal cone, poor contact in the center electrode assembly | Replace spark plugs with known good ones or check at a special stand [SRT]. (The absence of external damage and sparking between the electrodes on an inverted candle does not allow us to conclude that it is working) | Replace faulty spark plugs |
Weakening or breakage of the springs of the weights of the centrifugal regulator of the ignition distributor, the damper rings of the weights are lost, jamming of the weights | Visually and on a special stand [STO] | Replace ignition distributor |
Fuzzy operation of the vacuum ignition timing controller: when the vacuum is removed, the plate does not return to its original position, large play in the bearing | Inspection. The characteristic of the vacuum regulator is taken on a special stand [STO] | Eliminate jamming, replace faulty vacuum regulator or ignition distributor assembly |
Eliminate jamming, replace faulty vacuum regulator or ignition distributor assembly | The gap between the throttle valve and the walls of the mixing chamber is visible through the light | Use the stop screws on the shutters to close them completely. In this case, the dampers should open easily, without jamming. After adjusting the screws fill with paint |
The carburetor dampers are mounted on skewed axles and do not close at any position of the stop screws | Inspection | Leaning the damper axles on a suitable stop (not to bend them), loosen the screws and, after correctly orienting the shutters, tighten them [HUNDRED] (or replace the carburetor or throttle body) |
Ingress of foreign objects under the throttle valve or parts of its drive | Inspection | Remove foreign object, check damper operation |
[K] - only for cars with a contact ignition system
[B] - only for cars with contactless ignition system (installed on some cars since 1988)
[STO] - work is recommended to be done at a service station
* - installed on parts of engines