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Q: Loses power when reaches a certain speed limit sometimes it works sometimes it doesn't when it works cruise control works

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I put the code tester up and it told me my O2 sensor was bad is that the cause I don't really know what causes my car to work when it does work but when it doesn't it loses power at 35 and it will put then it will go back to the 35 and does it again sometimes it does it at 45 mph as well

My car has 142000 miles.
My car has an automatic transmission.

A: Hey there. This may likely be related to a ...

Hey there. This may likely be related to a bad O2 sensor. As you may know, the O2 sensor monitors the oxygen content of the exhaust gases as they leave the catalytic converter to determine how much additional fuel to add or subtract to the air/fuel mixture. When this sensor is not working properly, you may experience poor running conditions as a result of the car being over or under fueled depending on the circumstances. This may cause the car to starve for fuel or be flooded with too much fuel. I would recommend having an expert from YourMechanic come to your home to take a look at your car to properly diagnose the loss of power and move forward with repairs.

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