Excessive Emissions or 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 Speed Control (ISC) valve and Throttle Opener Control System.

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

Poor or contaminated fuel ^ Check for excessive alcohol content.
^ Recommend higher grade fuel.
^ Drain fuel tank and add clean fuel