High CO at High RPM

DEFINITION
Abnormally high Carbon Monoxide with low or normal Hydrocarbons during cruise (2500 rpm)


POSSIBLE CAUSE ACTION

Canister purge system Check EVAP System.





[1][2]PCV malfunction Check PCV system.
Testing and Inspection



EGR malfunction Check EGR system.
Testing and Inspection



Restricted exhaust Check - Catalytic converter.
- Exhaust system for collapsed/
pinched pipes and muffler damage
Testing and Inspection



Incorrect Spark Advance Check Spark controls (EST ESC)




Vehicle remains in Perform O2 sensor test
Open Loop at steady throttle Testing and Inspection
(2500 rpm)



Fuel Injection system Check - Fuel pressure
Chart A-6 Fuel System Diagnosis
- Regulator operation
(check vacuum line and return hose)
- Service Fuel Injector (Pressure cleaner)