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Q: The rpm drops when stopped. It feels like it wants to die then catches to normal, it will do this a couple of times.

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No check engine light is on, and my Verizon Hum isn't picking anything up either. I have replaced the crankshaft sensor, spark plugs, battery, PCV valve and it still does it. It also has a problem starting when the temperature is between half and 0 degrees. Nothing else is wrong with the car, perfect condition. I just can't figure out the drop in rpm when stopped. And it starts doing it when it's warmed up. There is hesitation when I press the gas after the rpm drops too. Any advice would be appreciated, thanks.

My car has 80000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. I would recommen...

Hi, thanks for writing in. I would recommend checking the idle air control valve which is what regulates intake air as it is mixed with fuel at idle and upon slowing down to an idle speed. When this is not functioning properly, it can cause the RPM’s to fluctuate and hesitate when accelerating from a stop. It is a common problem.

If you would like further help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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