High CO at High RPM

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

POSSIBLE CAUSE ACTION

Faulty canister purge system Check Fuel Evaporative System under
TESTING PROCEDURES.



[1][2]PCV malfunction Check the PCV system under TESTING
PROCEDURES.




EGR malfunction Check the EGR system under
TESTING PROCEDURES.




Restricted exhaust Check the Catalytic Converter under
TESTING PROCEDURES.



Incorrect Spark Advance Check the Spark Controls. Refer to
COMPUTERIZED ENGINE CONTROLS.



Verify vehicle remains in Refer to COMPUTERIZED ENGINE
Closed Loop at steady throttle CONTROLS for Self-Diagnostic procedures.
(2500 rpm) and oxygen sensor
is working.