High CO - At High RPM

This condition indicates abnormally high Carbon Monoxide with low or normal Hydrocarbons during cruise (2500 rpm).

POSSIBLE CAUSE ACTION

Faulty canister purge system Check Evaporative System.


PCV malfunction Check PCV system.



EGR malfunction 1. Check EGR system.
2. Check EGR electronic controls.



Restricted exhaust Check Catalytic Converter.



Incorrect Spark Advance Check Spark Controls (SC).



Verify vehicle remains in Closed
Loop at steady throttle (2500 rpm)
and oxygen sensor is working.



Fuel Metering 1. Check Air/Fuel ratio, fuel pressure, and regulator operation.
2. Perform injector balance test.
3. Service fuel injectors (pressure cleaner).