High CO - at High RPM

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


POSSIBLE CAUSE ACTION

PCV malfunction Refer to Positive Crankcase Ventilation, Testing and Inspection


Restricted exhaust Refer to Catalytic Converter, Testing and Inspection



Fuel metering malfunction Check fuel pressure
Perform injector balance test
Inspect regulator operation
(check vacuum line and return hose),
Service Fuel Injectors (Pressure cleaner)
Fuel Delivery and Air Induction