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Q: RPMs fluctuating

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I have taken my car to many mechanics but can't seem to find the problem. My car starts fine, but when I start driving it randomly fluctuates between 500 RPMs and 1500 RPMs. I also sometimes get small surges, as if someone was pushing in the gas pedal. I will stall when stopped if I do not push the gas pedal. And the car will also begin jerking when the gas is pushed and released. None of this is consistent; it just happens randomly, daily, or weekly. I replaced the EGR valve and the idle control valve, but that did not solve any of the issues.

This sounds like there could possibly be a vacuum leak somewhere. My other guess is that the new idle air control valve may also be malfunctioning. If you switched out some parts lately, getting new car parts that are bad right out of the box is starting to become more common, especially with cheaper parts. I would recommend having a mechanic from YourMechanic come to you with their specialized diagnostic equipment to figure out why your car is stalling and acting up the way it has been.

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