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Q: Motor skips a beat only when idling.

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Hello!starts well drive for a while I stop at a red light when its idle the motor will skip a beat at least once.New battery new sparkplugs I have my oil changes regularly I alternate regular and high test gas the check engine light is not lit What could be the problem?

My car has 136000 miles.
My car has an automatic transmission.

A: Hello - most likely, the idle air control v...

Hello - most likely, the idle air control valve is a bit gummed up and is sticking ever so slightly when it becomes the key control at a stop light. Cleaning or replacing it should resolve the "stoplight stumble."

I would recommend having the idle control valve replaced by a certified mechanic, such as one from YourMechanic, who can come to your location to get your car back in working order.

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