High CO and HC at Idle

This condition, at idle, indicates abnormally high Carbon Monoxide and Hydrocarbons.

POSSIBLE CAUSE ACTION


VERY RICH AIR/FUEL MIXTURE

Rich operating condition Check oxygen sensor and feedback system
Leaking fuel injector(s) Refer to FUEL SUPPLY AND AIR INDUCTION/DIAGNOSIS, TESTING AND INSPECTION PROCEDURES/TESTING PROCEDURES/FUEL INJECTOR BALANCE TEST.
Excessive fuel system pressure Check fuel pressure regulator and vacuum hose.



Faulty Fuel Evaporative system Check Fuel Evaporative system. Testing and Inspection



Fuel in crankcase being Remove [1][2]PCV from crankcase
sucked through PCV valve and retest emissions. Testing and Inspection