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Q: SUV tries to accelerate and stop at same time

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My SUV acts like it wants to keep accelerating when I press on the brake pedal to slow down. It has a jerking back and forward which causes a hard stop. It seems to want to accelerate and brake at the same time because the RPMs continually and constantly move up and down switching from V4 to V8 mode. The same jerking occurs when going up short inclines and also when driving downhill, forward and back until I completely stop. When starting and staying at a low speed of under 35 mph, my SUV can not maintain the speed; it wants to stop. It never has died fortunately, but I have to punch the accelerator for it to pick up speed. Recently I was in a slow-moving line, coasting about 10 mph and my foot wasn’t on the brake or the gas pedal. The vehicle kept moving forward on its own. The problem seems to always happen at low speeds from 0-40 mph. Every time I go to the dealership, they can not duplicate the problem because this problem is intermittent. This could be dangerous if my car won’t stop and causes an accident. Can you please give me your expert advice of how this can be solved?

Hello. Your vehicle is equipped with a throttle-by-wire system. This means that there is no physical connection between the throttle on the engine and the gas pedal. There is a sensor on the gas pedal that tells the computer how much throttle you are requesting. Depending on a number of factors, the computer will decide how much throttle to apply to the engine. If there is a problem with the sensor in the gas pedal or the electronic motor at the throttle body, you can experience the symptoms you are describing. I would recommend that you ask for help from one or more of the technicians at YourMechanic. They can come to you with their test equipment to inspect the stuck acceleration condition and advise you on a repair.

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