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


Restricted exhaust Refer to Catalytic Converter




Fuel metering malfunction Check fuel pressure. Refer to Fuel Delivery and Air Induction. Testing and Inspection
Inspect regulator operation
(check vacuum line and return hose),
Service Fuel Injectors (Pressure cleaner).