spdracer:
I am pretty sure you have a vacuum leak. Check all connections from the air filter to the intake manifold. Is the temperature sensor installed in the intake tube? Is the PCV hose connected to the intake tube? Is the IAC hose connected to the intake tube? Are the PCV and IAC hoses connected to their sources? A vacuum leak means that extra air getting sucked in and it is not measured by the computer. This causes a high idle and a lean condition. The IAC has a thin gasket that is easily ripped. If it is not 'perfect', it will leak. You might want to put a thin film of RTV sealant on the throttle body-to-upper plenum flange. Don't use much, just a film to fill in any imperfections in the mating surfaces. You can check to see if the t/b blade is closing completely because it should rest on the little black set screw (it should have some green paint or something on it to prevent it coming loose or being adjusted). Check that the range of opening is smooth and there are no sticky spots from fully closed to fully opened. The t/b has a coating from the factory that should not be cleaned with carb cleaner or brake cleaner, just a clean rag (wet or dry). FWIW, the computer measures the TPS voltage at start-up and uses this value as the zero/closed t/b position. The TPS can be off a little and it will still work OK. (If it is at 0.8 V, it's a problem).
HTH,
Chris