Q: Engine idle is too high

asked by on

The car rev counter is going up while is in neutral why

My car has 120000 miles.
My car has a manual transmission.

Hi There, This may be a sign of a vacuum leak or potentially a dirty or faulty idle control valve. High idle speed, stalling and hissing sounds are common signs 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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