Setting the ignition timing using a test lamp (BMW 3 Series E21)

Check if the ignition timing mark is in the middle of the clutch housing hatch. Make sure that the marks on the rotor and the distributor housing are next to each other.

Connect the test lamp with one wire to the low voltage terminal of the breaker and the other to ground.

Turn on the ignition.

Turn the ignition distributor housing in the direction opposite to the direction of rotation of the rotor, and then in the opposite direction until the contacts open, i.e. until the indicator lamp lights up.

Secure the ignition distributor to the engine in this position.

Turning the crankshaft, make sure that the indicator lamp lights up when the mark on the flywheel is in the middle of the clutch housing hatch.

Connect the vacuum hoses to the ignition distributor.

At the first opportunity, check the ignition timing dynamically.