Is replacing the IAC valve and cleaning the throttle body complicated?
No it is not. Definitely need to clean out the port for the IAC sensor. Best way for a good cleaning would be to take the TBI off the intake, take out the IAC and clean the whole throttle body with carburetor cleaner. Then you can check the throttle body base gasket to see if it is in good shape. Lot of times they would be bad.
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