Which parts fail
Components named in complaints (accelerator pedal, throttle, sudden acceleration, cruise control).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2009 Toyota Prius owners, lightly cleaned up (personal details are redacted by NHTSA).
I went to park in a parallel space when all of a sudden my ABS, (!), VSC light come on with the loss of brake power and a loud beeping noise. With this sudden loss of brakes in the middle of driving, I could have harmed myself and others in any cars around me because I also lost steering capability. This is a problem that there was an extended warranty for, but there should be a recall. My car is a 2009 and was only covered before the pandemic and now it is 2021 and I have no recourse, but to try and fork over $3500.00 for which I don't have. I am a second owner and this is a very common problem amongst Prius owners. I didn't have any other symptoms that I could point out prior to this situation. I have had my hybrid battery, engine, ecu and most recently a stolen catalytic converter replaced. This ABS actuator problem needs to be addressed for another 5 years with a free repair. …
When I am coming to a stop or need to put on my brakes my car will accelerate at a jump ahead pace As if to take off instead of slowing down and stopping. Regardless whether I'm turning a corner or I'm continuing straight when I have to Put on the brakes it speeds up instead.
Driver went to park and the brakes did not respond! In fact the vehicle went from 2-5mph to approx 30+ & kept picking up speed and went into storefront. Driver was able to wrestle vehicle into reverse and it went equally fast back into a parked car where it finally came to a stop. Hugely frightening and potentially lethal.
I pulled my Toyota Prius into my driveway, stepped on the brake, opened the garage door and waited for my husband to get out of the car. He opened the passenger side door and started to move his foot out the door but before he even got one foot out, the car surged ahead and ran into the garage, pretty much destroying all the storage units on the right side of the garage. My husband thinks the car was going between 35 and 40 MPH. Since my accident there have been two other incidents of toyotas accelerating independently in palo alto. One ran into a house on park avenue, destroying the front wall and front door of the house. A few days later, a Toyota ran over a curb, across a lawn and into a corner of a house on north california ave. …
My 2009 Toyota Prius was less than 4 months old. As I was parking in front of my apartment, I could feel the car still accelerating while I had already moved my foot to the brake. Braking as hard as I can I realized my car wasn't responding at all. The car climbed on to the curb into the grass, hit a light pole, tilted to its right side (I was parking to my right) and fell down on its side. I tried to turn the car off, but wont turn off. The wheels were still accelerating as I was trying to get out of the seat belt, called out for help and got out through the driver side window. I called 911. Police helped me turn off the vehicle; until that time, the car was still accelerating on its own. This seems to be a common issue with the Toyota Prius 2nd generation. This happens when the car is at very low speed (like in my case, while parking) or when its floored all the way. …
Tl* the contact owns a 2009 Toyota Prius. While applying pressure to the brake pedal at 10-15 MPH, the vehicle forcefully surged forward. The vehicle was taken to an authorized dealer for inspection. The technician was unable to duplicate the failure. The vehicle was taken to the authorized dealer on a separate occasion for the identical failure which there was no resolution. The failure mileage was 5,000. The current mileage was 10,000. The vehicle identification number was unavailable. Updated 2/26/10 the consumer stated the vehicle would surge at times upon starting the engine. It would also lurch while in park. The consumer stated there were 2 incidents where her foot was still on the brake and the vehicle accelerated which caused 2 minor accidents. The vehicle was taken to the dealer for electrical and brake work. However the vehicle continued to surge when started intermittently. …
Tl* the contact owns a 2009 Toyota Prius. The contact was driving the vehicle at approx 10 MPH, the vehicle suddenly accelerated as the driver's foot was on the brake trying to slow down. The vehicle in front was rear ended but the vehicle still did not stop accelerating so the driver swerved and hit a sign. There were no injuries reported at the scene, but after 3 people in the other vehicle reported injuries. A police report was taken at the scene. The contact took the vehicle to the dealership after the body repairs were done and the dealer inspected the vehicle. He was informed that they could find nothing wrong with the vehicle. He called the manufacturer and reported the problem. He was still awaiting a response at the time of the complaint. The current mileage was approximately 14,000. The failure mileage was approximately 5,000. Updated 03/12/10. Updated 09/30/10
I was involved in 2 identical accidents over the past 6 months with the same car, a 2009 Toyota Prius. In December '09 I was making a right turn to pull into a parking spot. I was completely in the spot and went to come to a full stop when my 2009 Toyota Prius suddenly accelerated and crashed into a car. Then again on June 21, 2010, I was making a right turn into a parking spot and the same car suddenly accelerated as I went to come to a full stop in the parking spot. This time the car jumped the curb and went through a chain link fence. Both times I was making a right turn into the spot, both times I was braking and both times the car accelerated as I went to come to a full stop. The dec '09 accident was reported to the police, the June'10 accident was not.
I just bought a 2009 Prius & there are so many issues with unexpected acceleration & vehicle not going into park or reverse just stops in neutral, I was at a heb sore trying to park, all of a sudden my car sped up an hit a pole in front of me, I was trying to park, with my foot on break, so as to slow down, yesterday I had my wife drive the Prius & the car suddenly stopped would not go into reverse or drive, that was very dangerous then they pull into a target parking lot I had to drive out there to meet them, it took almost 1hr & 3mins to get the car in reverse, off course I called my Toyota sales guy this being the third time I have reported this incident & the keep down playing it saying there is nothing wrong, not really looking into it.
My wife and I were driving down a residential street approaching a stop sign. There were two cars stopped at the sign. Several hundred feet from the stop, I took my foot off the accelerator. The car did not slow down. I stepped on the brake. The car did not slow down. I stood on the brake as hard as I could. The car did not slow down. I said to my understandably alarmed wife, we're not stopping. And we didn't until we smashed into the back of a tahoe stopped at the stop sign, doing major damage to the Prius that rendered it undriveable and perhaps totaled. My wife has a very sore back that I am hoping starts to feel better today or we will have to schedule a doctor's appointment.
Related recalls
Vehicle speed control › Accelerator pedal
Toyota is recalling certain model year 2004-2010 passenger vehicles. The accelerator pedal can get stuck in the wide open position due to its being trapped by an unsecured or incompatible driver's floor mat.
Remedy: Toyota filed an amended defect report on November 25, 2009, stating that dealers will modify the accelerator pedal and, on certain vehicles, alter the shape of the floor surface under the pedal.
Acceleration complaints in other Prius years
Frequently asked questions
How common are acceleration problems on the 2009 Toyota Prius?
NHTSA has 71 complaints about the speed control & acceleration of the 2009 Toyota Prius, 14% of the model year's 502 complaints. The component named most often is accelerator pedal (4 mentions).
Is there a recall for 2009 Toyota Prius acceleration problems?
Yes — NHTSA recall 09V-388 (accelerator pedal, Oct 5, 2009). Recall repairs are free at authorized dealers.
At what mileage do 2009 Toyota Prius acceleration problems start?
Half of the complaints with a recorded mileage happened before about 10,000 miles, and 78% before 25,000 miles.
Is it dangerous?
Owners linked 26 crashes, 0 fires and 13 injuries 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.