Q: My '65 F-100 lurches only when driven slowly.

asked by on January 21, 2017

My '65 F100, 4 on the floor, lurches when I drive slowly. It drives beautifully at high speeds, like when I have constant foot pressure on the gas pedal. Going through town on the other hand, when your foot is hoovering over the pedal, and lightly pressing it, my truck lurches quite a bit to the point that I often pop it in neutral and coast when I can. Sometimes I hear the drive train getting yanked around when I can't coast through town and am forced to let it lurch at low speeds.

My truck has 300000 miles.
My truck has a manual transmission.

Hi there. The symptoms that you are describing lead to the accelerator pump in the carburetor not pumping correctly at low rpm’s and low speeds. Try adjusting the carburetor settings to be 100 rpm’s higher and turn in the fuel 1/2 turn. This should help with the accelerator pump issue and keep your vehicle from lurching. If you need further assistance with your vehicle lurching at low speeds, then seek out a professional, such as one from Your Mechanic, to help you.

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