Idle Air Control (IAC) valve attaching screws.
IAC valve assembly.
CAUTION: If IAC valve has been in service: Do not push or pull on the IAC valve pintle. The force required to move the pintle may damage the threads on the worm drive. Also, do not soak IAC valve in any liquid cleaner or solvent, as damage may result.
CLEAN AND INSPECT
Clean IAC valve O-ring sealing surface, pintle valve seat, and air passage.
Use carburetor cleaner and a parts cleaning brush to remove carbon deposits. Do not use a cleaner containing methyl ethyl ketone, an extremely strong solvent, and not necessary for this type of deposit.
Shiny spots on the pintle or seat are normal and do not indicate misalignment or a bent pintle shaft.
If air passage has heavy deposits, remove upper manifold assembly for complete cleaning.
Inspect IAC valve O-ring for cuts, cracks, or distortion. Replace if damaged.
CAUTION: If installing a NEW IAC valve, be sure to replace with an identical part. IAC valve pintle shape and diameter are designed for the specific application.
Measure (only if Installing a New IAC Valve)
Distance between tip of IAC valve pintle and mounting flange (see image).
If greater than 28 mm, use finger pressure to slowly retract the pintle. The force required to retract the pintle of a new valve will not cause damage to the valve.
INSTALL OR CONNECT
Lubricate IAC valve O-ring with clean engine oil.
IAC valve assembly.
Attaching screws coated with appropriate thread-locking material.
Reset IAC valve pintle position: Disconnect negative battery cable for at least ten seconds to clear PCM memory.
Reconnect negative battery cable.
Start engine and check for proper idle operation.
CAUTION: The hardware used to attach the Idle Air Control (IAC) valve is coated with thread-locking adhesive. If any these parts are removed for service, inspect the attaching screw threads. There should be enough thread-locking material (adhesive or compound) on the threads to ensure proper relocking. If not, clean the threads and apply Loctite 262, or equivalent, to the threads before reassembly. Replacement screws are included in the service screw assortment package. New attaching hardware is included in the service packages.
Before you replace anything, get it confirmed the part is bad