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Q: Car revs high

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When I start my car it revs high and keeps building i have to start it and shut it off several times to get it to run nominal what could this be thanks

My car has 170000 miles.
My car has an automatic transmission.

It sounds like you may have a vacuum leak. High engine idle is usually a common sign of a vacuum leak. When a vacuum leak is present in an engine, this causes an excessive imbalance in the air/fuel ratio which creates a loss of power and causes the motor to run at a much higher RPM as a result of the increased oxygen present in the fuel charge being injected into the motor. I would recommend having an expert from YourMechanic come to your location to diagnose your vacuum leak as these can be very difficult and time consuming to trace.

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