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Q: Need help with a reduced engine power warning light.

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Came on about 3 weeks ago off and on. I checked sensors and everything. The codes read it was an accelerator peddle and a throttle position sensor. Took it in to get tested and was told my throttle body was going bad so I changed that. But still in the morning the light comes on. I was told it could be the accerator peddle going bad or spark plugs. Do you have any advice on what it could be?

My car has 186915 miles.
My car has an automatic transmission.

A: Hello. If the trouble codes for the throttl...

Hello. If the trouble codes for the throttle position sensor and accelerator pedal came on then those two sensors are the first things I would check. For this vehicle, the throttle position sensor is built into the throttle body.

If after replacing the unit the code remains, then it may be possible that there is an issue with the wiring or connector. It may also be possible that the accelerator pedal position sensor is bad. The sensor is located at the base of the accelerator pedal, and as it's name implies, measure pedal position so that the computer knows how wide to open the electronic throttle body.

If it goes bad it can set off the warning light as well as cause performance issues. In more serious cases it's failure may even render the vehicle undrivable. If you are unsure, I would recommend having a professional technician, such as one from YourMechanic, come to your location to diagnose the cause of the warning lights so that this can be repaired properly.

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