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
System Performance Test Chart Identification
DFI SYSTEM PERFORMANCE CHARTS
| Chart | Test Condition |
|---|---|
| DFI SYSTEM CHECK | DFI System |
| A1 | "ENGINE CONTROL SYSTEM" Light Inoperative |
| A2 | "ENGINE CONTROL SYSTEM" Light On |
| A3 | No Start Or Stall After Start |
| A4A | Fuel System Diagnosis |
| A4B | Fuel Pressure Out Of Range |
| A5 | Injector System Diagnosis |
| A6 | Oxygen Sensor Not Ready |
| A7 | Lean Exhaust Diagnosis |
| A8 | Rich Exhaust Diagnosis |
| A9 | Oxygen Sensor Diagnosis |
| C1 | ECM Replacement Check |
| C3 | Canister Purge Diagnosis |
| C4 | EST System Check |
| C6 | AIR Management Diagnosis |
| C7 | EGR Diagnosis |
| C8 | VCC Diagnosis |
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.
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