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Q: My car keeps shutting off for no reason

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I'm curious? My uncle put in my alternator because I needed a new one and ever since then my car keeps shutting off out of no where? What could that be? I just got it out of the shop for all the recalls to be fixed and I had the oil changed.
My car has an automatic transmission.

A: Hello. There are a number of reasons why yo...

Hello. There are a number of reasons why your car will act like this. The most common cause of this is either a failing crankshaft position sensor, a fuel pump issue, or a failing ignition control module. This should not have anything to do with the alternator replacement unless the battery is not charging and it is draining. I usually install a scan tool and check the sensor readings first. I check to make sure that the crank sensor is reading correctly. If it is then I check the fuel pressure to see if it is falling off. If it is then the fuel pump or pump circuit may be bad. If that is fine then the ignition module needs to be removed and tested as that is the most likely issue. If you want to have this fixed, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose this.

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