Car kept accelerating, would not brake or stop, kept accelerating in idle too

Today I was driving my sister’s car that had just come out of the shop. I was following her to a gas station just a street or so down.
I did not notice any issue turning on to the street, but as I was going down this short stretch of street I noticed the RPMs were accelerating, as was the car, even after letting off the gas.
I began trying to brake normally, but the brakes had a great deal of force, and wouldn’t allow me to slow it much. I managed to slow it down to 10mph, and was trying my best to get the brake down more, as I was just a few meters from barreling through an intersection.
I had no time to try and slow it down at that point, I had to throw it into park going 5-10mph while the RPMs kept shooting up. I managed to call my sister in a hurry, saying “the car won’t stop”, just before I had to push it into park.
She pulled over just prior to me, as she noticed me going to the side of the road multiple times trying to stop (I had to dodge a lot of parker cars so I couldn’t stay to the side).
From the spot that I realized it wasn’t braking to the spot where the stop sign was was a very small stretch so unfortunately I had no time to slow down any other way.
As a considerably new driver I freaked out and wasn’t sure if I should use the emergency brake or not, but now I feel like it would’ve been better.
Finally stopped safely, my sister came over to the car and we called the auto shop, just a street away. They asked her to try to start it and see how it went. She started the car and the RPMs immediately shot to 4-5, sucking up most of the remaining gas. She turned it off and they came out to check it. They restarted it, and it revved up many times once again as it sat there in park. It was taken back to the car shop.
The mechanic put gas in it and checked it out again, test drove it, and handed it back.
The car just had the fuel pump replaced, and they said that sometimes Chrysler’s computer do a reset, and that it being so low on gas made the computer go crazy and push the engine or something.
Any how, it ran fine after that, and but the experience was very alarming and left me with a lot of questions.

  1. Will this happen again? My current car is supposed to be replaced with this car so I worry about the longevity of it after this. I was going to keep my other car just in case of course, but this has become a question of safety more so than reliability at this point.
  2. The mechanic didn’t say I had done any damage, but could I have harmed anything forcing it into park going up to 10mph?
  3. Is there any other info or tips on something like this? I still don’t truly understand this.

Sorry for the long post, tried to give a fair amount of details.

You should have put it in NEUTRAL. Checking the throttle cable for binding is what I would do.


Depending on the year of the Chrysler, the problem might have been caused by faulty Idle Air Control valve.

The IAC valve controls the engine idle speed whenever the accelerator is released.

Sometimes these IAC valves will go to the wrong position for the idle condition. Causing the idle speed to go thru the roof.

I had a coworker have the IAC valve malfunction in their vehicle while pulling into a gas station.

In their case, the vehicle took out two gas pumps.


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It is a 2004.
Could that be what caused the car to accelerate rapidly while I was driving it?
The high idle didn’t start until after the random acceleration happened while I was driving.
I had only been going about 20mph as I was on a residential road, but when it started accelerating I let off the gas and tried to brake, but the acceleration continued. After it got checked out the mechanic said the high rpm was preventing me from braking properly.
Was it similar with your friends car?
It definitely sounds like his situation ended up pretty rough!

The engine does have an IAC valve.

Be careful, If the IAC malfunctioned once, It’ll do it again.


This must have been quite scary, sorry you had to experience that. And good for you for keeping you and everybody else safe. I’ve never had that happen to me, but if it did I’d try to put the trans in N, coast to the side of the road, then turn the key to “off”. It’s easier to think of that from where I’m sitting that where you were though. there was a moderately sized earthquake here a few days ago, and I completely forgot what to do as it was occurring … lol … so I know how an unexpected emergency situation like that can affect a person.

Other ideas for the cause, get a flashlight & check the throttle pedal area to see if carpets or mats could be preventing free motion of the pedal, and if there is anything loose or broken, missing spring etc, in the throttle pedal area. Hopefully your shop has checked for broken missing springs in the engine compartment throttle body area.

Several posters have suggested you put the car in Neutral (N) if this happens. The engine will race, but that’s not a problem if the car is in N. You will be able to steer and brake and coast out of the roadway. In fact, try it the next time you are driving. On a quiet street just push the control from D to N. It should move easily, no need for brakes or pushing buttons. No harm will come to your car.

Cars do not have emergency brakes, they have parking brakes.

Emergency brakes implies they will stop a car in an emergency, they won’t

You were in a panic situation with an out of control car, yet you were able to make a phone call ?

Happy you lived through it.

And like has been already mentioned, if something like this ever happens again, put it in netrual

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