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Q: Why does my car lose power at 20 miles an hour and 60 miles an hour and my check engine light goes on and off

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Sometimes when I'm driving I get to 20 miles an hour and the car starts to lose power then it picks back up after I cut the car off and cut it back on then when I'm getting up to 60 miles an hour does the same and when I cut the car off and cut it back on I get all the power again what's my problem

My car has 154000 miles.
My car has an automatic transmission.

A: Hello. It sounds like you may have a sensor...

Hello. It sounds like you may have a sensor issue going on with your car. Most of the time when something like this occurs it is caused by a throttle position sensor that is not working properly. It can also be caused by worn out fuel system or ignition system parts but it is most commonly a sensor. I will usually install my scan tool and drive the vehicle while monitoring what the sensors are doing. This would tell me if there is a sensor issue going on. If the sensors are reading correctly then I inspect the ignition system and also test the fuel pressure. If you are looking to have this loss of power checked, consider having a YourMechanic certified technician come to your home or office to diagnose why it is losing power.

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