When starting goes to 2000 rpm the drops to 1100 and stays?

1995 SATURN SC1
190,000 MILES • 1.9L • 4 CYL • MANUAL
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TOM2699
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when starting goes to 2000 rpm the drops to 1100 and stays.
1. removed throttle body, tps, aic, and cleaned did not replace tps or aic.still them same plus now i have a check engine light.
2. someone said check for vacume leaks none found, when u check for leak at air intake do they mean where body bolts up? gasket was fine. will wait for advice. tks
Feb 28, 2014 at 12:12 PM
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SQM
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Hello,

High idle typically due to a faulty idle air control valve.
Keep in mind that if the IAC is faulty then cleaning it will not fix the issue. If the pintle spring is too weak it will allow more air to pass through that it is supposed to and that will lead to high idle.

https://www.2carpros.com/articles/engine-idles-too-high

As for the vacuum leak on the base of the intake manifold, the best was to test it is to spray carb cleaner at the base where the gasket is. If there is leak, then the engine will react to the cleaner and will idle high. It will go back down when the chemical burns off.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Please let me know if you have any questions.
Thank you.
Jan 10, 2022 at 7:16 PM