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Q: Why is my car accelerating by itself?

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I was driving my truck at a doctor's appointment and I was backing out the parking lot and it accelerating back and I almost thought that I hit a car. And it happened to my brother who was driving the truck and he said that accelerated on him too. I want to know why it is accelerating what I can do to fix it.
My car has an automatic transmission.

A: This vehicle engine has a manual throttle c...

This vehicle engine has a manual throttle cable and cannot accelerate by itself. You may have a faulty idle air control valve that can cause a high idle but is limited to only about 1250 rpm. I would recommend having the floor mat checked to make sure it is not obstructing the gas pedal in any way. If that's not the case, have the computer diagnosed by a certified technician, like one from YourMechanic, to see if there are any codes for the TPS or IAC. If anything comes up, the codes need to be diagnosed and repaired as necessary to fix this issue.

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