Q: Car self-accelerates intermittently

asked by on September 14, 2016

I purchased a used car and three different times (in one month) my car has self-accelerated. After it did this each time, there was a faint oil smell. The car had been sitting for 1 ½ years and before I purchased it, a full tune-up was performed. An oil change was also done and the following were replaced: air filter, muffler bracket, and front brake pads. Two weeks after purchasing it (used), problems began. Slowing down with my brakes while I was pressing on the brake pedal, the car just kept moving; so I slightly slammed on the brake pedal. Immediately following this, there was a faint smell of oil. Two weeks later, this same thing happened. Then today, my car self-accelerated while leaving a parking lot. This time, I did not use the brakes before the self-acceleration. Now… my brakes are squeaking. When the self-acceleration happens, it is always when below 10 mph. The brake light, ETS, oil check light, and check engine lights do not come on. No lights have ever come on. What do you think is causing the self-acceleration and what will solve it?

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Hello. The odor of oil is merely coincidental to the symptoms you report. Any vehicle of that vintage is going to have multiple oil leaks unless the engine has been re-sealed or re-built. Just be sure the leak is not onto a hot manifold which would create a known fire hazard. The unintended acceleration could be caused by anything from sticky, binding linkages to electrical control issues. In case it gets worse before you have this resolved, just remember the cardinal rule when it comes to unintended acceleration: turn the key OFF but DO NOT move the key into the position that will lock the steering column thus preventing you from steering off the road to a safe spot. If you would like to have this checked, a qualified professional from YourMechanic can come to your car’s location to inspect the acceleration problem.

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