Excessive Exhaust Emissions/Odors

SYMPTOM:
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
Proceed to ADJUSTMENT PROCEDURES


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


Fuel Injected Check air/fuel ratio, Refer to
COMPUTERS AND CONTROL SYSTEMS,
check fuel pressure


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