Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1990 Audi 100 Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Ignition Timing
Ignition timing, idle speed and idle mixture are closely interrelated and MUST be checked/adjusted together. See IDLE SPEED & MIXTURE in this article.
4-CYLINDER IGNITION TIMING
| Application | Degrees BTDC @ RPM |
|---|---|
| Checking Value | 4-8 @ 780-900 |
| Adjusting Value | 5-7 @ 780-900 |
5-CYLINDER IGNITION TIMING
| Application | Degrees BTDC @ RPM | |||
|---|---|---|---|---|
| 2.2L Turbo (M/T) (1) | TDC @ 750-850 | |||
| 2.3L |
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| Checking Value | 13-17 @ 720-860 | |||
| Adjusting Value | 14-16 @ 720-860 | |||
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Factory Service Tools
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.