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Q: The car revs while not moving, the check engine light is on

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The check engine light is on, on the Head-up Display of my car. It revs up and down when the car is not moving. I checked the cylinders as I was told at the dealership that if they misfire, this can happed. I checked that out and the same problem happened. I also had the transmission fluid changed but to no avail. I took it to the shop again and they told me it is the intake manifold causing this. I would like some advice and another opinion about the cause of this issue. Thank you.

A: Hello. If the engine speed is going up and ...

Hello. If the engine speed is going up and down as the vehicle is sitting there and running, then it is not a transmission problem. It can be an intake manifold issue as they mentioned, as I have seen a lot of these fail and cause this. Most of the time though, it is caused by a faulty air flow sensor. When this is not reading right, then the computer cannot control the idle. I would scan the computer for codes to see for sure what the computer is seeing. If you are going to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose your Check Engine Light and proceed with appropriate repairs.

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