Vacuum Retard Angle, Checking

Vacuum retard angle, checking

- Connect vacuum tester VAG 1368 or equivalent according to manufacturer's instructions.
- Disconnect plugs from idle stabilizer control unit and connect together.
- Start engine.
- Pull off hose from vacuum advance unit.
- Check ignition timing; if necessary adjust to 5° ATDC.
- Pull off hose from vacuum retard unit.

Check with TDC sensor:
- Add 5° to indicated retard angle.
- Compare with specifications on chart for retard end.

Checking with timing light:
- Shine timing light on timing mark again and bring mark back to original setting by turning knob on timing advance tester.
- Read off retard angle and compare with specifications on chart for retard end.

- Reconnect vacuum hose to vacuum unit.
- Reconnect plugs to idle stabilizer control unit.