Re: High Engine RPM on Startup
This could have to do with the TPS, but also with the idle air control (IAC) stepper motor. A dirty air passage from the IAC can give idle problems.
Remove the IAC stepper motor and clean the plunjer and air passage very well.
You will have to remove the resonator box for this, because the passage starts at the front of the throttle body. You could run some throttle body cleaner through the air passage with the engine running.
If you have a scanner which shows live data, you could see the TPS sensor % and check if there is any change to the figure while starting.
If you donīt have such scanner, but you do have an Android phone, then you could download the free app "Torque" and just buy a cheap bluetooth dongle and there you go. Besides many live data figures, it will also show you fault codes from the PCM and give you the possibility to errase the PCM fault data. Very handy and cheap scanner (at least if you have the Android phone already).