Q: Car runs rough until warm, and then runs fine.

asked by on December 22, 2015

The car runs roughly upon startup. Once the engine warms up, the car idles normally.

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I would have a technician inspect your rough idle. He will probably also check for codes on the computer. It may be the air temperature sensor malfunctioning if it idles rough only when it’s cold. You may be able to remove it and clean it or replace it. If that doesn’t fix it, it may need to be checked out by a technician.

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