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.



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