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Q: Car not accelerating and doesn't always start

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My car is not accelerating past 20 MPH. It goes very slow and shuts off when idling. The car also doesn't start sometimes and I have to sit and wait until it does.

Your issue sounds like it could be a failed fuel pump in its last moments of life. With lack of fuel the vehicle will run very poorly and will not be able to accelerate and won’t be able to run at idle unless kept running with the gas pedal. Your issue could be coming from multiple other things as well. The vehicle could be in what is called "limp home mode" which is where the computer controlling the engine management system sees a serious problem that, if left alone, could cause major engine damage. The computer will enter this mode to keep catastrophic failures from happening. A proper diagnosis of your accelerating issue should be carried out to find the cause.

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