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Ghost Gas Pedal

The Wife called and frantically told me her car was in the middle of the road and would not run. I quickly drove out there to help her out. To my surprise it was quite the opposite. Her car would not stop. I started it up and the brake was really stiff and not affective at all. Emergency brake worked though. Later that night I drove it home about 2+ miles in all. Right away I noticed the car just wanted to take off on its own. The car would just keep gradually accelerate with out the gas pedal engaged. I only let it go to about 30-40 max without applying the brakes and emergency brake. Along the way, I would just put it neutral and do the double brake thing, it was more effective. During a neutral stage I decided to rev the engine to see what would happen. It seemed normal, but from that point on any time i would put it in neutral it would rev higher. (no tach, so i would guess 2-3 thousand RPM based on sound. When stopping now, I would just shut the car off in neutral. Turn it back on in neutral and it would start to rev at the same 2-3 and sometimes drop back off to normal and sputter and some times it would just stay rev’d. I never let it just rev for a long time in neutral cause it seemed to just slowly increase, so once it got to a certain pitch i just shut the car off and tried again.

2001 Plymouth Neon/Auto/89k

The tale of the ghost gas pedal.

-SwitchTrack-

Sounds like a stuck throttle cable.

Thanks ill look into it a little later. Just trying to get some ideas floating around with this thread. I can only hope it’s the throttle cable. If not the cable could the throttle its self be stuck. Without looking at it, some kind of retention spring worn or broke?

Based on the higher revs and hard brake pedal, I would guess a vacuum leak either in the power brake booster or the line providing vacuum for same.

any tips on checking vacuum pressure? sound logical, I was originally thinking she had burnt up brakes cause of the added force working against her, but no smell of burning brake fluid present.

Make sure the throttle body is not all gummed up.

will do

Recall 983 was for replacement of the brake booster vacuum hose. The original hose was not oil resisant and will swell, collapse or fall off at the manifold connection.

The throttle body is attatched to the air cleaner and connected to the intake manifold with a flexable rubber hose. If someone left the hose clamp loose the hose will pull loose from engine torque/movement. As you try to drive with the intake hose loose the engine speed will increase/decrease from engine movement. When the PCM detects a large intake leak it will shut down the engine, this may be what your wife experienced.

Thank you all for the Help. Those of you that suspected a vacuum problem were spot on. Nevada that is exactly what happened. The brake vacuum line from the master cylinder to the exhaust manifold swelled and popped off. I have a hose clamp on it for now. Will look into the recall in the morning. Thanks for all the great input.
SwitchTrack

Thanks for reporting back. It’s always nice to hear if we’re right or wrong here!