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Q: Car idling erratically

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As soon as I start my car, it idles erratically.

A: Hello. The erratic idling could be caused b...

Hello. The erratic idling could be caused by several things: You could have a bad mass air flow sensor, the throttle position sensor could be bad, or the idle air control valve could be bad. This could also be an indication of a problem with the fuel system, or a very bad vacuum leak in the engine. I suggest you have all of these possible issues checked as soon as possible because they all could make the car idle erratically. A diagnostic test of the erratic idling would best be done by a certified technician, like one from YourMechanic.

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