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 Check Air/Fuel ratio,
perform injector balance test,
inspect regulator operation
(check vacuum line and return hose),
check fuel pressure





Malfunctioning air pump Check air injection system




Faulty Fuel Evaporative system, Check fuel evaporative system
vapor lines, purge solenoid
and valves



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



Engine misfire with Closed Loop Perform Self-diagnostic procedure
fuel metering, causing system
to go full rich