Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2012 Ford Mustang owners, lightly cleaned up (personal details are redacted by NHTSA).
Recently started having erratic shifting issues. Will downshift randomly out of nowhere while driving. Sometimes will just be stuck in 1st gear and won't go anywhere until I pull over and shut off/start up again. Dangerous because I never know when it will do it. Might seem like everything is fine and then all of a sudden, it downshifts and loses power. Rpm's rise but car has no power. Have to figure out how to get out of the way. As stated in ford's " Customer Satisfaction Program 16N02," my 2012 has all the symptoms and I have DTC code P0731 but dealer refused to service my vehicle because it doesn't show up with my VIN, even though it's a 2012 and I clearly need my Molded Leadframe replaced.
Speedometer went to zero while driving and seemed to be in neutral. Could not accelerate. Also low fuel warning light came on when I had a full tank. After car was shut off and restarted speedometer seemed fine for about 1 mile, then self accelerated. Now continues to read zero and can not accelerate unless I restart engine.
In 2012 or 2013 I had an accident caused by unintended acceleration. The Mustang ran into the back of semi truck. Unattended acceleration happened twice in the same day and the second time I could not get it to break free and stop until the last second but it was too late it hit the semi truck trailer in front of me. This was inspite of me having both feet pushing strongly on the brake pedal. We had started off slowly from a red light and then the car downshifted and took off. Southwest Ford in weatherford, tx had called the Ford engineer to come look at it. It took a month for him to come. He looked at it in its banged up shape and declared that there was no problem. When I got the car back something had changed. It seemed like the software had been changed because it never had the problem again and whenever the brake was touched it would kill any acceleration immediately. …
Tl* the contact owns a 2012 Ford Mustang. While pulling into a parking space at a very low rate of speed, the vehicle suddenly experienced unintended acceleration. The vehicle crashed into a pole and a building. No injuries were reported and a police report was filed. The cause of the failure was not diagnosed. The vehicle was towed and not repaired. The manufacturer was notified of the failure. The failure mileage was 7,700.
Issue # 1 brakes: upgrade "brembo" brakes squeaked about 2 weeks out the dealership. Took it a total of 4 times and dealer could not find the issue, the 5th time, I drove the vehicle and showed service advisor and tech. According to dealer the rear brakes were replaced. The next day, brakes are still squeaking, take it back to dealer where it was repaired a second time, picked up the car, on the 4th day, I was coming to slowing down ready to brake, pushed the clutch and car jolted forward (as if I pushed the gas and let go of the clutch). I did not think anything of it, 5 minutes later, the car started grinding, noise was only heard when driving and would stop as the vehicle came to a stop. …
While entering the freeway in rush hour traffic, my car went into "limp mode", the wrench light came on as did the check engine light. I had to pull over on the shoulder of the freeway, turn the engine off and restart it. This has happened a couple of times in the past couple of days- mostly while driving on the freeway. It is very scary to be driving on a houston freeway, have this happen and need to safely maneuver a vehicle to the shoulder of the freeway, often crossing several lanes of traffic when vehicles are moving at 40-55 MPH and I have no ability to accelerate. I have also had to stop in the middle of the freeway to restart my car because I was not able to safely change lanes. It was a terrifying experience and I was afraid I would be re-ended by motorist driving at posted speeds. …
My vehicle constantly goes into limp home mode while driving. Turns off all cylinders except 1 which let's you drive about 5mph. Also while my vehicle is at idle it begins to loose proper idle RPM and nearly stalls until revs back to a higher RPM. After some research I found that the issue is thought to be the throttle body and throttle body sensor. Currently mymy vehicle is at the dealership going through some vehicle diagnostics to figure out the exact problem. They told me it is not covered under the vehicle warranty and I am being charged $145.00 for the initial inspection and then charged by the hour to fix the problem, I not including parts. My vehicle only has 59,000 miles on it and it's already failing. It appears that numerous people are have this issue and Ford has yet to recall affected vehicles.
Tl* the contact owns a 2012 Ford Mustang. The contact stated that while driving at various speeds and idled, while the accelerator pedal was depressed and the vehicle failed to accelerate. The contact stated that the wrench warning was displayed (power train fault). The contact stated that he used a diagnostic machine and received an unknown code. The vehicle was taken to oxmoor Ford Lincoln 100 oxmoor ln, louisville, ky 40222, phone number: [phone] where the failure could not be replicated. The vehicle was not repaired. The manufacturer was notified of the failure and stated that the VIN was not part of the recall but did not offer any further assistance. The failure mileage was 50,000.
I was driving my car and it just went into a idle mode barely moving a light came on it look like a tool checked in my manual and it was the electronic throttle light I was driving in heavy traffic going to work had to make to were I could turn off the highway barely made it it could of cause an accident I looked up on line and nccc had a petition on the problem with the electronic throttle Ford does not have a recall instead they extended warrant but I onlyhad the car for about 6 months and no extended warranty it has 180,00 miles on it I could of cause an accident I think Ford should replace this its a known fact that the electronic throttle is a problem with fords
I was driving in the expressway at 60 MPH when suddenly my car lost power on the acceleration. A wrench tool appear and the dashboard on the RPM clock ... At that moment the car desaccelerate almost to 30 MPH and I was unable to gain speed. I went to a side of the road, turn it off and restarted the car. Everything appear to be normal but the first thing I did was go to the dealer. They run a test on it and told me that the problem was related to the electeic throttle body. I dont understand how is possible to happend something like that when my car barely has 4 years. There is no warranty on ot and the repair for it is really expensive.
Acceleration complaints in other Mustang years
Frequently asked questions
How common are acceleration problems on the 2012 Ford Mustang?
NHTSA has 35 complaints about the speed control & acceleration of the 2012 Ford Mustang, 7% of the model year's 469 complaints.
Is there a recall for 2012 Ford Mustang acceleration problems?
No. NHTSA lists no speed control & acceleration recall for the 2012 Ford Mustang, though it has 6 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2012 Ford Mustang acceleration problems start?
Half of the complaints with a recorded mileage happened before about 39,000 miles, and 50% before 25,000 miles.
Is it dangerous?
Owners linked 3 crashes, 0 fires and 1 injury to speed control & acceleration problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.