Chart 22

Exhaust System Concerns

Odor (Sulfur, Rotten Egg Smell)

NOTE: A slight sulfur smell may be normal. Catalysts with less than 8,000-16,000 kilometers (5,000-10,000 miles) (new vehicle or replaced catalyst) are likely to have a sulfur smell due to the highly active state of new catalysts. Replacing the catalyst can actually make the symptom worse.

SYSTEM/COMPONENT	REFERENCE ( PINPOINT TEST - CNG, FLEX-FUEL & GASOLINE ) unless noted
Check for any driveability or exhaust smoke symptoms	Refer to STEP 2: NO DTC(s) PRESENT SYMPTOM Chart INDEX for direction to repair other symptoms.
Fuel Delivery System	Natural Gas Applications: GO to B: Natural Gas Fuel Delivery System STEP HB1. All Others: GO to C: Fuel Delivery System STEP HC1.
EVAP System	GO to X: Evaporative Emission (EVAP) Monitor and System STEP HX14.
Fuel Source	Talk with customer. Since sulfur content can vary in different fuels, suggest trying a different fuel source.