Remove the distributor cap.
It is more convenient to adjust the gap on the distributor removed from the engine, but after that you will have to re-set the ignition timing.
To check the clearance on the distributor, not removed from the engine, we turn the crankshaft to a position in which the stop of the movable contact is on top of the roller cam (maximum gap between contacts).
Check the gap with a feeler gauge (0.35–0.45 mm).
If it differs from the prescribed, then to adjust it..
... loosen the screw securing the contact group with a screwdriver..
...and an adjusting screw. For convenience, the slider can be removed (see Replacing the distributor rotor).
Attention! When unscrewing and tightening the screws of the contact group, do not press hard on them, as the bearing of the movable breaker plate can be damaged.
By moving the plate of the contact group, set the required clearance and tighten the adjusting screw. Once again making sure that the gap is correct, we also tighten the contact group fastening screw.