High idle

1996 DODGE INTREPID
178,000 MILES • 3.5L • V6 • 2WD • AUTOMATIC
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ROBSL
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  • 3 POSTS
My car has been doing this high idle for a while. I have replaced all the vacuum hoses and MAP and IAC but to no avail. I'm starting to wonder if it maybe the ECU? Not sure where to go from here.
Jun 10, 2019 at 10:28 AM
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SCGRANTURISMO
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Hello,

A high idle is usually a vacuum leak. A vacuum leak is going to be anything from the Mass Airflow Sensor (MAF) to the combustion chamber and includes the intake air duct, throttle body gasket, intake manifold gasket, vacuum lines, EVAP lines, and the vacuum lines, if any, that are going into the dash for the HVAC System. Pay special attention to the intake manifold gasket as this is the most likely culprit. I have included a link below for you to go to.

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

Please go through this guide and get back to us with what you find out.

Thanks,
Alex
2CarPros
Jun 10, 2019 at 1:05 PM
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ROBSL
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The gaskets are all good and new. All air lines are new. No codes thrown.
Jun 10, 2019 at 2:30 PM
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STRAILER
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If there are no vacuum leaks you are on the right track with a bad PCM or corrosion at the main connector to the PCM if okay I would try a used/rebuilt unit. here is a the location so you can check it out. Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.
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Jun 12, 2019 at 4:20 PM