Because, the engine to run fast or the pedal to stay down even after you've moved your foot from it.
Disconnect the engine. If you drive along and you car seems to keep on accelerating in spite of lifting-off the gas pedal, disconnect the accelerating engine from the driving wheels. 1  In a manual car, press down on the clutch. 2  In an automatic, flick the transmission into neutral. A sticking gas pedal can be the result of damage to the throttle cable, gas pedal assembly, or even the throttle body or carburetor. Finding the Fault. Start by examining the gas pedal assembly. Move it by hand while observing its movement. Look for any binding of the pedal arm or linkage. Next, open your car's hood and locate where the throttle cable travels through the firewall. Have a helper move the pedal and observe the cable. When driving, it might happen for the gas pedal to stick due to a wide range of either mechanical or electronic issues. This situation can occur and has occurred in a broad selection of car models over time. By Aaron Turpen, Tue, February 21, 2012. The gas pedal (more properly called the accelerator) can sometimes begin to stick on a car, causing the engine to run fast or the pedal to stay down even after you've moved your foot from it. This is a dangerous situation, but is often easily fixed. Red_Hayabusa/iStock/Getty Images. A sticking gas pedal can be the result of damage to the throttle cable, gas pedal assembly, or even the throttle body or carburetor. Make a few visual checks to determine the cause of your sticking gas pedal.
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why does my gas pedal keep sticking