Excessive Exhaust Emissions (Odors)

DEFINITION: Vehicle fails an emission test or vehicle has excessive "rotten egg" smell. (Excessive odors DO NOT necessarily indicate excessive emissions).

Carefully perform a visual and physical check.
Perform "DIAGNOSTIC CIRCUIT CHECK."

CHECK:

- EGR valve not opening.

- Vacuum leaks.

- Faulty coolant system and/or coolant fan operation.

- Remove carbon with top engine cleaner. Follow instructions on can.

If emission test indicates excessive O2, check for items which cause car to run lean or too hot.

If emission test indicates excessive HC and CO or exhaust has excessive odors, check for items which cause car to run RICH.

- Incorrect fuel pressure. Use CHART A-7.

- Fuel loading of evaporative vapor canister.

- PCV valve plugging, sticking, or blocked [1][2]PCV hose. Check for fuel in crankcase.

- Catalytic converter lead contamination (Look for removal of fuel filler neck restrictor.)

- Improper fuel cap installation.

- Faulty spark plugs, plug wires, or ignition components.