Excessive Exhaust Emissions (Odors)

Definition: Vehicle fails an emission test. Vehicle has excessive "rotten egg" smell. Excessive odors do not necessarily indicate excessive emissions.

POSSIBLE CAUSE ACTION


Incorrect idle speed. ^ Check Idle Air Control (IAC) valve. Testing and Inspection
^ Check Throttle Valve Minimum Position.


Fuel in crankcase. ^ Determine cause (flooding, excessive cranking etc.).
^ Change oil and filter.

Fuel Metering ^ Check air/fuel ratio. (Verify O2 Sensor Voltage).
^ Check fuel pressure.

Faulty fuel cap ^ Replace fuel cap.

Lead contamination of catalytic converter. ^ Check for missing fill pipe restrictor.
^ Replace catalytic converter if contaminated.

Poor or contaminated fuel. ^ Check for excessive alcohol content. Alcohol/Contaminants-In-Fuel Testing Procedure
^ Recommend higher grade fuel.
^ Drain fuel tank and add clean fuel.