why does my 92 topaz have an extreme high idle in park when car is warm
I know the question is a year old, but if it helps someone, great!! 99 out of 100 times its the TPS (Throttle Position Sensor)...very typical... Many of my families' Tempo/Topaz's developed the exact same issue at usually around 15 or so years old, idle was good in Drive, but as soon as the car was put in Park, the RPMs would shoot up to 3,000. Scanned the computer for free,(never pay for this, if the garage wants your business, they'll do it for free) or like us we have invested in our own scan tool, which can be had for less than the price of 2 scans at most shops, lol. Installed a new TPS and they all idled like new, not to mention taking the "Check engine" light off! :)
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