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Q: Engine shuts off when slowing down or at a complete stop.

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I have replaced the EGR valve, the oxygen sensor, and the alternator. Once I replaced the alternator, it stopped cutting off while driving. Now, it only cuts off when I'm slowing down or when the car is idle. When it did this a little under a year ago, they said it was my harmonic balancer. It was shaking violently to the point that it wasn't triggering the crank shaft sensor. They replaced the harmonic balancer and it worked fine until about a month ago when it started shutting off again. They threw me code after code and I fixed all of them to be point that no codes are thrown. And it is still shutting off. HELP!

My car has 148280 miles.
My car has an automatic transmission.

A: Hello, thanks for writing in. This can be c...

Hello, thanks for writing in. This can be caused by a number of things. From the symptoms that you have though I would start by checking the throttle body. If it is very dirty then the throttle plate may be sticking which will cause this to occur. If the throttle body is clean then I usually check the idle control valve to see if it is functioning as designed. If that is fine also then it may be a bad crank sensor. These will fail and act like this. A scan tool would be needed to watch the signal when this occurs to see if it is bad. If you would like 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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