Q: What would cause acceleration without stepping on the gas while stopped?

asked by on

While stopped in traffic with foot on brake my jeep started accelerating, spinning the back tires. Used both feet to brake until it would no longer hold causing jeep to lunge forward--resulting in an accident.

My car has 14000 miles.
My car has an automatic transmission.

It would be hard to pinpoint the exact cause. A couple of possibilities could be a vacuum leak. If the engine is sucking in too much air, it could raise the engine speed, possibly drastically if a ;large vacuum leak suddenly occurred, such as the brake vacuum booster line breaking or coming loose. Another possibility could be in the throttle control. Most of today’s engines, do not have a mechanical connection (throttle cable) between the gas pedal and the engine. This is done with potentiometers, sensors, and switches. Think dimmer switch on a ceiling light. Sensors on the gas pedal, tell the engine control unit exactly how far you’ve pushed the gas pedal. This then sends a signal to the stepper motor on the throttle body, which open the throttle in the same amount as you have pushed the gas pedal. A short or defect in any part of this system could have caused your situation.

Have it towed to the nearest Jeep service department as soon as possible for further inspection. You may want to contact Jeep Customer Service and notify them of what occurred.

Was this answer helpful?
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  1. Home
  2. Questions
  3. What would cause acceleration without stepping on the gas while stopped?

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Won't start after warmed up.

Hello. If the vehicle starts after being allowed to sit for a while, then it may be possible that the issue is heat-related and goes away once the car cools down. If the vehicle will start with starting fluid, then...


Hello. A transmission that will not shift into park can be caused by a wide variety of issues. A few common causes are a faulty stoplight switch, a bad shift solenoid, or perhaps an internal transmission issue. The stoplight switch...

Q: First gear in my transmission has a bad problem

The manual transmission on your Jeep Wrangler has one of two problems. The shift boot may be getting in the way of the shifter, blocking it from going all the way into first. This could cause it to pop...

Related articles

How Do Power Car Windows Increase Passenger Safety?
Power windows are responsible for approximately 2,000 emergency room visits every year. When a power window closes, it exerts enough force to bruise or break bones, crush fingers, or restrict an airway. Though...
What Causes Hoses to Leak?
While the largest part of your engine is mechanical, hydraulics plays a significant role. You’ll find fluids at work in a number of different areas. Your car's fluids include: Engine oil Transmission...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.