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.
2003 Pontiac Sunfire StandardFACTORY OEM SERVICE PROCEDURE
Powertrain Control Module: Installation
- Remove the new PCM from the packaging and check the service number to verify the number is the same number, or an updated number, as the faulty PCM.
- Push the PCM into the PCM bracket. The retaining tab will lock in place.
- Install the PCM harness connectors and lock down the release levers.
- Connect the negative battery cable. Tighten to specification. See TORQUE SPECIFICATIONS .
- Program the PCM. See PROGRAMMING
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.