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.
1989 Cadillac Seville BaseFACTORY OEM SERVICE PROCEDURE
Fixed Spark Mode (Setting Ignition Timing)
- Initial base timing is set by jumpering pins "A" and "B" together at ALDL connector, while NOT in diagnostic mode. The ALDL connector is located near brake pedal, just below dash. See Fig 1 .
- Set timing to specification shown on EMISSION CONTROL LABEL. Jumpering pins "A" and "B" together will cause a "SET TIMING" message to appear on CCDIC. This indicates that ECM is in set ignition timing mode.
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Disclosure: Verified tool recommendations may earn an affiliate commission at no cost to you.
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.