Brake must be engaged to start/run
My 2004 Grand Prix lost engine power while driving,
it simply will not run of my foot isn't on the brake.
The car will moved if I ride the brake while pressing
the gas. It starts up just fine as long as my foot is
on the brake. Any fixes you know of?
The only thing on the brake pedal is the brake pedal position switch. It is part of the shift interlock system, which affects the starter circuit. But none of those would prevent a running car from staying on. Is the problem that your car won't remain running unless you are constantly giving it gas?
The only thing that dictates if it runs or not is if the brake is engaged. Gas or no gas the car runs like normal. Without the brake engaged the car dies.
It's an electrical problem of some sort, a switch, a sensor, or possibly even a broken or shorted wire sending bad signals or no signals somewhere. You probably need professional help by a shop that's fairly expert at diagnosing electrical issues.
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