High CO and HC - at Idle

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

POSSIBLE CAUSE ACTION
Fuel Metering Check Air/Fuel ratio, check fuel pressure, inspect regulator operation (check vacuum line and return hose), Perform Injector Balance Test, Service Fuel Injectors (Pressure Cleaner)


Malfunctioning air pump Check Air Injection system, under TESTING PROCEDURES.


Faulty Fuel Evaporative system, 1. Check Fuel Evaporative system
vapor lines, purge solenoid under TESTING PROCEDURES. If OK step 2
and valves 2. Check Evaporative System electronic controls. Refer to COMPUTERIZED ENGINE CONTROLS.


Fuel in crankcase being Remove PCV from crankcase
sucked through PCV valve and retest emissions



Engine misfire with Closed Loop Refer to COMPUTERIZED
fuel metering, causing system ENGINE CONTROLS.
to go full rich for rich trouble code,
check fuel feedback (Oxygen sensor)