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 and adjust idle speed, refer to Adjustments

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

Fuel Metering ^ Check fuel pressure,
^ Check air/fuel ratio (O2 Sensor Voltage)
^ Perform Injector Balance Test
^ Check vacuum line and return hose

Faulty fuel cap ^ Replace fuel cap

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

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