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.
1987 Chevrolet Chevette L4-98 1.6LFACTORY OEM SERVICE PROCEDURE
Engine Control Module: Service and Repair
1. Disconnect battery ground cable.
2. Disconnect numbered and lettered connectors from ECM.
3. Remove ECM mounting hardware, then the ECM from the passenger compartment.
4. Reverse procedure to install.
NOTE: Replacement ECM's are not equipped with engine calibration units (PROMs). If the PROM is to be reused, care should be taken when removing it from defective ECM. See Prom, Replace for proper removal procedure.
Factory Service Tools
Use the Manual With the Right Hardware
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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.