On hot days, when backing out of parking spaces, the car has sometimes "surged" meaning that there has been unintended acceleration without the accelerator being pressed at all. I have had to suddenly and firmly put my foot on the brake to prevent the car from hitting other vehicles. This has happened on several occasions in August of 2012. I own a 2006 Ford Five hundred also and it has had the same problem in the same conditions (filing separate complaint).

- Diamond Springs, CA, USA

Rough acceleration from stop for years. After 218,000 miles engine shuts off reporting engine fail-safe mode. Will restart after sitting on side of road for couple, 5-minutes. Dealer states bad throttle body - $900 repair. Apparently a common problem.

- Fernandina Beach, FL, USA

The contact owns a 2005 Ford Five hundred. The contact stated that while driving 65 mph the vehicle stalled. The vehicle was taken to a dealer who diagnose that the throttle body sensor needed to be replaced. The vehicle was not repaired. The failure and current mileage was 138,000.

- Southville, MI, USA

Out side air temp was approx 96 degrees so ac was on. While shifting into reverse the vehicle lunged so hard it was uncontrollable, and unstoppable, if some one had stepped out behind me they would have died as I could only stop reward movement by shifting into drive. This occurred three times trying to get out of a parking space at a crowded mall.the vehicle then stalled. The lunging was so fast the brakes could hardly hold the car from moving in reverse. In checking there is a service bulletin tsb-05-25-13 from Ford Motor Company on this very issue but no recall, also many incidents/accidents recorded in this regard. If I was not prepared enough during this incident in a crowded parking lot some one would have died, this must be addressed B-4 someone is run over. Currently Ford has no comment. Please contact me for further details.

- Markleeville, CA, USA

After having turned onto a 35 mph street, having only reached 30mph, the RPM's shot up to six and the car accelerated to almost 40 without the gas peddle having been pressed. If there were another car stopped or a person in front of us they would have been hit. Another time the vehicle was at a stop light and again with out warning the cars RPM's shot up to about six. If my foot had not been applied completely to the breaks I would have been in a busy intersection resulting in the car having been totaled, death of more then one person. This is not safe.

- Black Diamond, WA, USA

The electronic throttle body is bad in majority of vehicles in my class year. This costly repair causes the vehicle to lunge forward while in drive and lunge backwards while in reverse. It is worst when the ac is on, ,it causes the vehicle to idle high and low to the point of almost shutting off the vehicle in traffic.

- Baltimore, MD, USA

We were driving down a highway and went to get back to speed after passing through a speed zone. I noticed a decrease in power and looked at the information screen. The fail safe mode and the "wrench" icon was on. I pulled the car over and turned it off. I then turned it on and the car acted normal. It has happened twice since the first incident. My wife took it to the dealership and Ford cannot duplicate the problem and the issue does not throw a check engine code or leaves any type of electronic history of the issue. I cannot allow my wife to drive this car because she is seven month pregnant and cannot have her drive it if the car breaks down due to this issue.

- Bastrop, TX, USA

This happens frequently almost daily in the summer. But on a hot day (90+) when moving from a stopped position out of a parking spot or around a corner, when you lightly have the brake pedal depressed if you turn the wheel slightly (ie backing out of a tight parking space) the car will lunge violently and aggressively in what ever direction you are traveling, sometimes so aggressively it will stall the vehicle out and then go into a failsafe mode. This is very dangerous as you could unexpectedly hit someone walking around the car at a stop sign or crosswalk. I have also found numerous other complaints on various blogs, forums, and other sites. Everyone basically stating the dealer gives them the run around. And as long as it is a hot day I can duplicate the results continuously, and would be more than willing to show this to someone else if possible. I am typically not one to complain, but I feel very strongly about the safety of this vehicle, especially since I have a 3yr old daughter.

- Port Wentworth, GA, USA

The contact owns a 2005 Ford Five hundred. The contact stated that while driving 5 mph, the engine light began to illuminate. The vehicle was taken to the dealer for diagnosis and the contact was informed that the vehicle would need a new throttle body. The vehicle had not been repaired. The failure and current mileages were 101,934.

- Camden, NJ, USA

The contact owns a 2005 Ford Five hundred. The contact stated that the transmission failed. Upon shifting into gear, the vehicle accelerated on its own even with the brakes applied. The vehicle would then enter into fail safe mode and stall. The failure would recur upon restart. There were no lights illuminated on the instrument panel. The vehicle was taken to a dealer for inspection and they stated that the failure was due to a throttle body failure. The throttle body needed to be replaced. The vehicle was not repaired. The manufacturer was not notified. The failure mileage was 50,000.

- Mentor, OH, USA

The contact owns a 2005 Ford Five hundred. The contact stated that while driving 55 mph, the check engine warning light illuminated as then vehicle decelerated independently. The contact was unable to increase speed and eventually, the vehicle stalled. The vehicle was towed to the dealer for diagnosis and the contact was informed that the throttle body would need to be replaced. The manufacturer was notified but offered no assistance. The failure and current mileage was 62,000.

- Edgewater, FL, USA

The contact owns a 2005 Ford five-hundred. The contact stated that while reversing from a residential garage, the vehicle lunged backward. The vehicle was not taken to the dealer. The manufacturer was not made aware of the failure. The vehicle was not repaired. The VIN was not available. The failure and current mileage was 70,000.

- Shrewsbury, MA, USA

During warm weather with the A/C operating, the rpms surge and the vehicle lunges in the direction of the transmission lever selection (forward or reverse) when moving the shift lever from park to drive or from park to reverse with driver's foot on the brake. Engine rpms surge up to approx. 1,500 from idle at a dead stop without input from accelerator pedal. Different indicator lights come on and often the engine dies after the surge. If driver does not keep appropriate pressure on break pedal while shifting from park, the vehicle will accelerate without input from gas pedal. This surge also happens when decelerating to a stop. Vehicle slows down and rpms decrease to approx 600 (idle), and with pressure applied to brake pedal, engine rpms will increase, without input from accelerator pedal, forcing the driver to increase pressure on brake pedal or risk uncontrolled forward movement. Initial reports indicate a faulty throttle body as referenced in NHTSA investigation # PE110818.

- Verona, WI, USA

Throttle body malfunction. Engine reves up while placing the car in drive or reverse without touching the gas pedal, up to 1.5 on the RPM's on the speedometer. This is very scary, a child crossed in front of me while I was waiting at a stop sign. Foot was on the brake but all of a sudden it just reved up. It lunged forward and I hd to really put that break on. Scared me and the child to. I bought the car new and had all service done from the Ford dealer in the service person there told my husband that this part "throttle body" was made by the same manufacturer that made the Toyota parts that went bad "sticking gas pedals" ? and that Toyota recalled this dangerous issue and fixed it. Unless my husband misunderstood this gentleman, which I don't think he did. I spoke to Ford and placed a complaint and they told me that there had been complaints, but there was no recall issued as yet, but hold onto my receipt in case there is a recall issued in the future. This will cost $850, "which I feel should be picked up by Ford". pressing normally on the breaks is not good enough, you have to almost put it to the floor so that you do not move and pray that it doesn't lunge forward in the transition from break to gas pedal. Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6)

- New Port Richey, FL, USA

The contact owns a 2005 Ford Five hundred ltd. The contact stated that while driving 20 mph, the vehicle started to lunge forward and backward before stalling. The contact merged the vehicle to the shoulder, turned the engine on and off and the vehicle started immediately. The fail safe mode warning light started to illuminate. The dealer was notified of the issue but the vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 83,000. The consumer stated before she started driving on the road, she backed out of a parking space. She had her foot on the brake slightly as she was backing up, when the vehicle tried to lunge forward then backward. She applied the brake all the way, stopped the vehicle, but did not turn it off and the fail safe mode warning light illuminated. She tried to back up again, but it still wasn't running correctly, but she managed to finish backing out and straightened out the vehicle. The fail safe mode light stayed on. She sat for a minute and began to exit the parking lot. She only drove 500 feet, when the incident happened again. Updated 10/01/12

- Milton, NH, USA

My wife, son and I were driving. The vehicle had random acceleration while at full stopped. About 10 minutes later after a full stop the vehicle had another acceleration while foot on brake and the vehicle stalled out. Once stalled out the computer displayed the following error "fail safe engine". after doing an online review I noticed that many other Ford Five hundred owners having the same issue and seems to be caused by "throttle body". please note that whenever the vehicle is on park and put into reverse, the higher acceleration takes place. I always have to be extra careful. I have to be extra careful while driving as I am afraid for acceleration and stalling out in the middle of the road.

- Telford, PA, USA

I notice years ago that when I would be backing up or pulling into a parking spot that my car would want to accelerate or just speed up. I would be barely pressing on the brake because I was letting the car use it's idleness speed to back out of the space or pull into the parking space. My husband thought it was because I was using the adjustable foot pedal. He does not drive the car very much. Shortly after this all started we purchased me another car, I stop driving my Ford 500 very much. It sits in the garage a lot. I let my daughter use the car once and she complain of the same thing happening to her and how it scared her. I am also scared of it and only drive it in emergency and I always try to be prepared to expect this to happen. It has no pattern of when or how it happens it all unexpected, working properly one minute and speeding up the next. This car has one other issue when it rains it leaks we find water in the floor on the driver side floor. This car is available for testing if needed because we have a 2nd car that I drive because of this issue. We keep it because it is paid for.

- Belton , SC, USA

Since 2007 the car intermittently will periodically lung forward and it is almost impossible to control the car. This has happened several times since June 2007 (88,000 miles). Even hard braking does not necessarily stop the car...I have had to put the car in neutral the engine revs up as if I am touching the accelerator (and my foot is not on the pedal) and I shut the car off. Turning the car back on does not necessarily remedy the problem. In addition, the car routinely goes into fail safe engine mode or cuts off while I am driving at a reasonable rate of speed both on rural roads and highways. This car is a hazard to drive, more so in the warmer months...my thought is something must get overheated but what I do not know.

- Deptford, NJ, USA

This has happened multiple times (meaning more than 5 times) during the summer of 2011. Driving on highway at posted speed limits and car suddenly lurches then drops into failsafe mode (as indentified by alert posted on the dash). Pull over, read owner's manual. Follow directions how to clear failsafe and implement them. A few times it worked for short periods of time. Other times, it would not work at all. Twice the car was running at approximately 65 mph and suddenly go into failsafe mode then stall out. Especially during street/city driving, car suddenly kicks forward then failsafe and will sometimes stall out in middle of street. Unable to restart. Last time this occurred car required towing to local Ford dealer. Initially said it was the throttle senor for a cost of $300. When I ok'd that repair, the dealership called back later and stated it was the entire throttle body and repair would come at a cost of $1000. The car now sits in my driveway where it was towed to and sits for safety reasons. After researching the internet, I have come to find that this is a common occurrence with Ford and an announced recall should be implemented immediately.

- Altoona, PA, USA

Driving in town, at approx 25mph. Car jerked/lurched suddently, then entered limp home mode. Pulled over, turned off car. Restarted and check engine light came on. Turns out it is a throttle body failure. Shop says this is a very dangerous situation - the car could suddenly accelerate/decelerate without notice. Looking at online forums - it seem a fairly common failure, and something Ford should issue a safety recall on.

- Wausau, WI, USA