High CO - at High RPM

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

Condition: High Carbon Monoxide, normal or low Hydrocarbons during cruise (2500 rpm).

POSSIBLE CAUSE ACTION


Faulty canister purge system Check Fuel Evaporative System.

Restricted exhaust Check Catalytic Converter.

EGR malfunction Check EGR system.

[1][2]PCV malfunction Check PCV system.

Initial timing incorrect Check base timing.
SEE Ignition System/ ADJUSTMENT PROCEDURES.

Check cam timing.

Incorrect Spark Advance Check Spark Controls.
SEE Ignition System/ TIMING SPECIFICATIONS

Fuel Injection malfunction Check fuel pressure.
Perform injector balance test.
Service Fuel Injectors (Pressure cleaner).