1999 Ford Mustang Acceleration Problems

Which parts fail

• Cruise control
  5
• Accelerator pedal
  2
• Linkages
  2

Components named in complaints (accelerator pedal, throttle, sudden acceleration, cruise control).

Mileage when the problem started

• Under 25k
  117%
• 25k–50k
  233%
• 50k–75k
  117%
• 75k–100k
  00%
• 100k–150k
  117%
• 150k+
  117%

Owner reports

Selected complaints filed with NHTSA by 1999 Ford Mustang owners, lightly cleaned up (personal details are redacted by NHTSA).

Tl contact owns a 1999 Ford Mustang. The contact stated that after making a left turn the vehicle suddenly accelerated to higher speeds. When he tried to apply the brakes, the vehicle continued to accelerate and he crashed into an embankment. A police report was filed. The contact was injured due to him immediately ejecting from the vehicle. The vehicle was towed to an independent mechanic and a diagnostic test was pending an investigation. The failure and current miles were approximately 134,000.

Unpredictable problem. Occasionally, 5 to 15 seconds after I first start my 1999 Mustang gt, the engine will rapidly increase in RPM and then return to normal. If the car is in drive or reverse and I do not have my foot firmly on the brake, the car will jump forward or backward. I notice the problem mostly when I first put the car in reverse. It May happen 3 or 4 times in one month and May not happen again for 2 or 3 months. If you do not have the brake applied firmly, I think the car could easily jump 5 feet before getting a foot on the brake. I currently have 29,000 miles on my car. I purchased it new in the middle of 1999. This has been a problem since the car was new. During a previous in warranty repair, I told the dealer about this problem and that sometimes it also had a rough idle. They could not reproduce either of the problems during testing. …

Pre-accident conditions: daylight, raining, car stopped at red light. A few minutes prior to arriving at the red light the driver's power seat moved all the way forward completly on its own accord after stopping at the red light I re-adjusted the driver's seat and when the light turned green I proceeded making a right turn in my normal "old lady" fashion. About 3/4 through the 90 degree turn the rear wheels lost traction and began to slide to the left. I immediately hit the brake and turned the wheel to the left. (I suppose it is possible that I accidently hit the cruise control button located on the wheel at this time). Anyway the car engine contiued to rev and the rear wheels continued to spin, driving me into a complete 360 degree turn, all the time with my food hard on the brake pedal. …

Tl* the contact owns a 1999 Ford Mustang. The contact stated that while driving at approximately 70 MPH with the cruise control engaged, the vehicle failed to decrease in speed when the cruise control was deactivated. The contact also stated that the brake pedal was applied, but the vehicle failed to stop. The contact shut the engine off while driving in order to stop the vehicle. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure and informed that the VIN was not included in NHTSA campaign number: 99V062001 (vehicle speed control). The approximate failure mileage was 165,000.

Consumer had an accident due to a defect with the cruise control speed cable as mentioned in recall 99 v 062 001. This vehicle was not part of recall due to VIN. Consumer states the cruise control was set at 53 MPH, consumer attempted to hit the brakes after seeing a vehicle stopped, but the vehicle would not slow down, and consumer hit the other vehicle, consumer suffered neck injuries.

While pulling out of a parking lot vehicle suddenly accelerated and crashed into rear end of another vehicle. Consumer had brakes applied in an attempt to stop vehicle, leaving skid marks on road. Manufacturer informed consumer that his vehicle was not included in any recall for throttle control cable. Please provide any additional information/attachments.

Driving at 75 MPH on cruise control. Needed to slow down so tapped brake pedal. Cruise would not release. Hit brake pedal again. No response. Pounded brake pedal and finally cruise cancelled. Dealership found cause to be a broken wire on the brake light switch. Luckily had room in traffic to handle the problem. Next step was to hit cruise off button.

While at a stop light and applying accelerator pedal to make a left turn, vehicle commenced to accelerate, and steering wheel locked up, causing vehicle to hit a van. Upon impact, both air bags did not deploy. Dealer was notified. Feel free to provide any further information.

I was driving south on I-85 with the cruise control set at 65 on a clear day. The vehicle went into a skid, and before I could stop the skid I hit the guardrail. There has been a recall on the cruise control for my vehicle (recall 99s09) which I believe contributed to this accident.

Consumer was trying to make a left turn at about 10-15 MPH, and suddenly wheel would not turn. Vehicle accelerated and ran into some trash cans, and some other stuff on sidewalk. Contacted dealer, and dealer tried to fix problem but with no success.

Related recalls

Acceleration complaints in other Mustang years