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.
1988 Chevrolet Spectrum ExpressFACTORY OEM SERVICE PROCEDURE
Diagnostic Codes
DIAGNOSTIC CODES
| Code | Definition |
|---|---|
| Code 12 | No distributor reference pulse to ECM |
| Code 13 | O2 sensor circuit is open (lean fuel condition) |
| Code 14 | CTS voltage signal low |
| Code 15 | CTS voltage signal high |
| Code 21 | TPS voltage signal high |
| Code 22 | TPS voltage signal low |
| Code 23 | MAT sensor voltage signal high |
| Code 24 | VSS malfunction |
| Code 25 | MAT sensor voltage signal low |
| Code 31 | Turbocharger wastegate control malfunction |
| Code 32 | EGR system control malfunction |
| Code 33 | MAP sensor voltage signal high |
| Code 34 | MAP sensor voltage signal low |
| Code 42 | Electronic Spark Timing (EST) malfunction |
| Code 43 | Detonation sensor malfunction |
| Code 44 | Lean exhaust indication |
| Code 45 | Rich exhaust indication |
| Code 51 | MEM-CAL failure |
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.