Warning! If you have the slightest doubt about self-diagnosis, remove the towline.
Serious repairs to a damaged engine will cost more than the services of a towing vehicle.
Engine knocking zones:
Engine knocking zones
1. The knock of the main bearings is very dangerous; stop the engine immediately, you will have to go to a car service or garage in tow. Low tone knock. It is audible in the lower part of the cylinder block, noticeably increases under load and with an increase in speed. Often its appearance is accompanied by a drop in oil pressure (The oil pressure warning light is almost constantly on).
2. The knock of connecting rod bearings is very dangerous; stop the engine immediately, you will have to go to a car service or garage in tow. The sound is rhythmic, ringing, metallic, medium tone. Significantly increases with increasing load and completely disappears when the spark plug is turned off.
3. The sound of piston pins is dangerous; without loading the engine, you can drive to a car service or garage on your own. Rhythmic, high tone with a sharp metallic tint, audible in all engine operating modes and intensifies with increasing engine load. Completely disappears when the spark plug is turned off.
4. The knock of worn pistons and cylinders is harmless; without loading the engine heavily, you can independently drive to a car service or garage. A sound reminiscent of the clatter of pottery. It is especially well heard on a cold engine, as it warms up it decreases or disappears.
5. Knocking valves is not dangerous, you can drive to a car service or garage on your own. A metallic thump against the background of a general muffled noise. It is well audible at low and medium speeds of the crankshaft from the side of the cylinder head above the valve locations. Valve clatter is often confused with tappet clatter (the latter - a very high tone and variable in volume - is practically unavoidable).
Detonation knocks are dangerous, but are usually eliminated by installing a later ignition. If you do not load the engine heavily, you can drive to a car service or garage on your own. Voiced metallic knocks that occur, as a rule, during acceleration of the car. The reason is incorrect ignition setting, the use of low-octane fuel, engine overload with too early upshift, significant carbon formation in the combustion chambers. Ignition needs to be adjusted (see section «electrical equipment») and apply a special fuel additive to remove carbon deposits on valves and in combustion chambers.