Had 'racing idle 2000rpm+.
He tried replacing the ISC, no change.
He had me look at it and within minutes caught that the coolant temp sensor was pegged at -47C *and* the TPS wasn't working (showed 0% throttle position through a sweep test).
Now...the TPS was restored simply by unplugging it and cleaning the terminals after which the idle speed came down. Leaving merely a rich condition/improper advance timing until the new coolant sensor arrives and is installed. I would have thought the racing idle was a result of the bad coolant sensor indicating an impossibly cold temperature
Sooo.. my question is: In the case where a bad or intermittent TPS signal could result in unintended acceleration at idle (google search on this model seems to locate owners complaining this can/does happen), might there a software update to address this which probably hasn't been applied to this specific vehicle...ie should I recommend he track it to a dealer to be updated?
Two codes stored were for symptoms (detonation/miss, and IAC which had been unplugged as it didn't race when that was disconnected)