Checking and Adjusting Ignition Timing Advance (Transistor Ignition System)
PROCEDURE

Alignment of Ignition Timing Mark on Flywheel with Mark on Clutch Housing 1 – ignition timing advance mark on flywheel; 2 – No. 1 cylinder TDC mark on flywheel; 3 – mark on clutch housing
Adjust ignition timing advance on a warm engine with idle speed correctly set, all electrical consumers switched off, and the cooling fan not running. PROCEDURE 1. Connect the timing light. 2. Start the engine and let it run at idle. 3. Aim the timing light at the inspection hole in the clutch housing after removing the plastic plug. Mark 1 on the flywheel must align with mark 3 on the clutch housing. If marks 1 and 3 do not align, loosen the distributor mounting bolt and turn the distributor until marks 1 and 3 align. Tighten the distributor mounting bolt. 4. Check the idle speed. 5. Check the ignition timing again. 6. Disconnect the timing light.
Test yourself
A quick Volkswagen Golf quiz: every answer comes with an explanation and a link to the manual page.