Q: My car is accelerating by itself.

asked by on October 01, 2017

I started my car earlier today and it vibrated and then stopped. I started its few more times and was able to drive it very slowly. Even with my foot down all the way on the pedal, there was very little acceleration. About 15 minutes later I tried again and it drove fine for roughly 500m but then it stopped accelerating and I pulled into a parking lot. I shut off the car, waited 5 minutes and started it again. With the car in park and my foot on the break, the engine began to rev as if I was repeatedly pushing my foot on the accelerator. I shut it off and 5 minutes later I started the car like normal and reversed 20 meters. I then put it in drive and slowly pulled forward with my foot pressed gently on the gas. Suddenly the car accelerated to ~4,000RPM and lurched forward and nearly crashed into the wall before I slammed on the break and shut it off.

Here is a video of the car accelerating while in park. My foot was off the gas during this.

https://youtu.be/XtUD2rk064U

My car has 85000 miles.
My car has an automatic transmission.

Engine idle speed is high Inspection $94.99 - $114.99 Get a Quote

Hi Conor. Thanks for contacting us today. In most cases, the issue of ’self acceleration’ is caused by one of the following; a damaged throttle body, vacuum leak, electronic throttle control, or idle control valve issue. This is a rather serious issue that should be inspected by a professional mechanic and resolved before driving the vehicle further and as soon as possible for safety reasons.

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