Lumina V6-204 3.4L DOHC (1991)
Idle Speed/Throttle Actuator - Electronic: Service and Repair
Idle Air Control (IAC) Valve Replacement
Idle Air Control (IAC) Valve
REMOVAL:
1.
Disconnect the IAC valve electrical connector.
2.
Remove the IAC valve attaching screws.
3.
Remove the IAC valve assembly.
CAUTION:On IAC valve that have 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 the IAC valve in any liquid cleaner or solvent, as damage may result.
Cleaning and Inspection:
1.
Clean the 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 that contains methyl ethyl ketone, an
extremely strong solvent, and not necessary for this type of deposit.
^
Shiny deposits on the pintle or seat are normal, and do not indicate misalignment or a bent pintle shaft.
^
If the air passage has heavy deposits, remove the upper manifold assembly for complete cleaning.
2.
Inspect the IAC valve O-ring for cuts, cracks or distortion. Replace if damaged.
3.
If installing a new IAC valve, be sure to replace with an identical part. The IAC valve pintle shape and diameter are designed for the specific
application.
4.
Measure the distance "A" between the tip of the IAC valve pintle and the mounting flange.
^
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.
INSTALLATION:
1.
Lubricate the IAC valve O-ring with clean engine oil.
2.
Install the IAC valve assembly.
3.
Install the IAC valve attaching screws and tighten to 3.0 Nm (27 lb.in).
4.
Connect the IAC valve electrical connector.
5.
Reset the IAC valve pintle position:
a.
Turn the ignition ON for five seconds.
b.
Turn the ignition OFF for ten seconds.
c.
START the engine and check for proper idle operation.
