Q: Irregular revving

asked by on August 20, 2016

Good day, when I start my car the revs goes to 2000rpm and slowly comes down. When I drive and stop at a traffic light it idles at 2000rpm. When I engage in a gear and release again it returns to just under 1000rpm. Also when I drive 40mph and remove my foot from the acceleration is feels like is jurks a bit. Please help. I have replaced the throttle body incl the TPS sensor as well as the MAP sensor. Regards

My car has 161500 miles.
My car has a manual transmission.

Is your Check Engine Light on? That may indicate that there is a diagnostic trouble code (dtc) stored. The code may help pinpoint which component requires further testing. Sometimes a dirty idle air control valve will stick during operation causing the symptoms you described. It may be cleaned and work okay, but most of the time it is best to replace it. Also, check to make sure that the gas pedal and linkages are not sticking. If you help testing this, a certified technician, like one from YourMechanic, will be able to diagnose the cause of the rough idling and jerking problem.

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