Q: Hello, when my car is in park or neutral it starts to accelerate on its own.
Yesterday I noticed that when my car is in park or neutral, the car will start accelerating on its own. For example, when Im in park the needle that sits on 1 starts to climb to 2 and then back down to 1. I drove it back home and every time I would ease up on the gas, the engine seemed like it was going to fall apart. Is this the idle air control valve or is it a sensor?
My car has 191000 miles.
My car has an automatic transmission.
It could be caused by several different problems like the idle control valve, engine vacuum leak, intake air filter clogged or contaminated mass air sensor or a sensor failure or engine just needs maintenance. I would suggest having the vehicle engine computer tested for codes and any other problems by a mechanic like one from YourMechanic so a proper diagnosis and fault found that can then be quoted and fixed.
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