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.
1990 Pontiac LeMans BaseFACTORY OEM SERVICE PROCEDURE
PCV System: 2.0L
- If engine is idling rough, check for a clogged PCV valve or plugged hose. Remove PCV valve from rocker cover with hose connected. Run engine at idle. Place your thumb over the end of the valve to check for vacuum. If vacuum is not present, check for a plugged hose, manifold vacuum port or PCV valve.
- Turn engine off and remove PCV valve. Shake valve, if valve does not rattle, replace PCV valve. Replace any plugged or deteriorated hoses. Excess blow-by is exhausted into the air filter and drawn into the engine.
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.