Excessive Exhaust Emissions (Odors)

DEFINITION
Vehicle fails an emission test. Vehicle has excessive "rotten egg" smell. Excessive odors do not necessarily indicate excessive emissions.

Perform "Diagnostic Circuit Check." Testing and Inspection

IF TEST SHOWS EXCESSIVE CO AND HC (or also has excessive odors),
check items which cause car to run RICH.

Check
- Make sure engine is at normal operating temperature.
- Fuel pressure. See Chart A-7. Chart A-7 Fuel System Diagnosis
- Canister for fuel loading. See Chart C-3. Chart C-3 Canister Purge Check
- Injector balance. See Chart C-2A Chart C-2A Injector Balance Test
- Positive Crankcase Ventilation ([1][2]PCV) valve for being plugged, stuck, or blocked PCV hose, or fuel in the crankcase.
- Spark plugs, plug wires, and ignition components.
- Check for lead contamination of catalytic converter (look for removal of fuel filler neck restrictor).
- Check for properly installed fuel cap.

If The System is Running Rich, (block learn less than 110)
Refer to the "Diagnostic Aids" section in "Diagnostic Trouble Code 45." DTC 45

If Test Shows Excessive NOx
- Check items which cause car to run LEAN, or to run too hot.
- Exhaust Gas Recirculation (EGR) valve for not opening. See Chart C-7. Chart C-7 Exhaust Gas Recirculation (EGR) Check
- Vacuum leaks.
- Coolant system and coolant fan for proper operation. See Chart C-12A. Chart C-12A Coolant Fan Control Circuit
- Remove carbon with top engine cleaner. Follow instructions on can.

If The System is Running Lean, (block learn greater than 150)
Refer to the "Diagnostic Aids" section in Diagnostic Trouble Code 44. DTC 45