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really awful
Crashes / Fires:
32 / 1
Injuries / Deaths:
10 / 0
Average Mileage:
10,714 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2010 Toyota Prius engine problems

engine problem

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2010 Toyota Prius Owner Comments (Page 4 of 14)

« Read the previous 20 complaints

problem #205

Jun 222010


  • 200 miles


Twice now my brand new 2010 Prius iv has failed to accelerate when I was driving. June 16 purchased the car. June 22 at a stop light on a surface street, continued on green light, car lost power in the intersection and I coasted to a stop. Restarted, and fine until August 3, 1443 miles on the car, when I stopped for gas, continued on to the highway, up to 65 mph, and car lost power again, would not accelerate, went down to 42 mph, and I coasted to the shoulder. Turned off power. Restarted, and fine again.

- Los Gatos, CA, USA

problem #204

Mar 132010

Prius 4-cyl

  • 1,700 miles
The contact owned a 2010 Toyota Prius. The contact was braking from 2 mph when the vehicle abnormally accelerated. The contact was unable to stop the acceleration as the vehicle crashed into the asphalt of a driveway. The contact sustained moderate injuries. The vehicle was towed to an authorized dealer. The manufacturer sent an investigator to further inspect the failure. The investigator stated that the brake and accelerator pedals were depressed simultaneously, causing the failure. The contact was advised there were no failures found in the vehicle. The contact refused to drive the vehicle and purchased a new vehicle. The current and failure mileages were approximately 1,700. Updated 11/19/10. The consumer stated she had no control of the vehicle, it just suddenly accelerated on its own. The vehicle jumped over a curb bordering the parking lot, then over a drainage depress/grass median through a sizeable shrub edge. The vehicle then slammed into a concrete sidewalk and down to the street curb, finally stopping with the motor off and having blown two tires. Updated 12/01/10

- Globe, AZ, USA

problem #203

Feb 012010


  • 5,000 miles
Toyota Prius 2010, my problem is sometimes the gas pedal does not release when trying to stop, I have found that by releasing the brake pedal the throttle releases, this always happens under the speed of 40 mph. This problem is always random, and you never know when it will happen, it has happened about 30 times so far, this started about 6 months ago. Is this problem part of the recall.

- Ocean View, NJ, USA

problem #202

Jul 312010


  • 4,200 miles


The cruise control disengage mechanism in my 2010 Toyota Prius does not disengage quickly enough when depressing the brake. I have to press the brake harder than any prior vehicles I have owned to kill the cruise control and if I release the brake before the cruise control is released then the car lurches forward. This is a safety issue with this vehicle and I called Toyota and they said that there is no safety issue and would not speak to me further about it without going to the dealer. The dealer had already told me that it is operating normally and that this is how the 2010 new Prius model year operates. I have a 2006 Prius as well and the cruise disengages normally. Many other people have experienced this issue and have documented their experiences on the forum They have even fixed the problem themselves by moving the cruise control disengagement closer to the top of the brake pedal. Others have reported that they can depress their brakes and slow down the vehicle without their brake lights coming on and this is the same problem because the brake lights and cruise control kill switch are linked together.

- Piedmont, SC, USA

problem #201

Jul 232010


  • 2,236 miles
Case of sudden unintended acceleration in a new 2010 Toyota Prius: I was parking my car in a pull-in parking spot in an office building parking lot. While straightening the car out in the spot, it suddenly accelerated out of control and jumped a curb in front of landscaped shrubbery. A large woody bush, and soft dirt stopped the vehicle. No one else was involved in the accident. The car has only 2200 miles on it. The car is currently being held by the dealer, Toyota Scion of eatontown, NJ.

- Monmouth Beach, NJ, USA

problem #200

Jul 272010


  • 18,500 miles
Was driving Prius 2010 model II with brake software applied by dealer about 1.5 months ago. Today (7/27/2010) I exited highway and began gentle braking on offramp, as suggested by manual to maximize regeneration. About half-way down offramp, I realized car in front of me was completely stopped and that I had to stop much more quickly than I was planning to. I don't recall being particularly distracted, but I can't rule out I noticed the stopped vehicle later than I should have. In any event, I'm not sure how hard I pressed the brakes, but I recall distinctly thinking "oh, my god. Nothing is happening" and 1-2 secs later I plowed into the car in front of me. The collision was hard enough to cause temporary pain to the driver in front of me, but no air bags were deployed and the Prius appears to not have major frontal damage - hood is bent back and maybe slight frame distortion => the impact clearly was not at the ~40-50 mph I was going when just exiting the highway, so some braking clearly did occur -- but I have the distinct feeling that my previous car (Subaru outbook) would have easily stopped in time. After accident, I tested brakes by going 15-20 mph in parking lot and braking hard. Always stopped quickly, I'm guessing w/100% friction braking. So brakes are probably not "defective" in sense of lost hydraulic fluid, etc... but I have never before experienced the feeling "I'm not stopping" except once when losing traction on icy road with a non-hybrid. The fact had time to think this thought at all probably means maybe 0.5-1.5 sec passed while braking ineffective. Checked for tire/skid marks on road or evidence of strong tire wear and found none, while I have on other cars when I have had to brake hard => Prius not braking hard despite emergency. Seem to have been caught in transition between regen & friction mode" this is still discussed in Prius forums -- software fix not good enough!" this is potentially very dangerous. Btw, car was in "eco" mode.

- Madison, CT, USA

problem #199

Apr 042010


  • 400 miles


New 2010 Prius ll commuter car suddenly accelerates or scoots when both feet are on the brake. The vehicle takes the same route to and from work daily. On every trip, when the right front wheel passes over a recessed manhole, the vehicle accelerates. I immediately push harder on the brake to stop the vehicle. The manhole is about 30 feet in front of an intersection, so I am already decelerating and braking when I cross over the manhole. This is scary because, if I the car doesn't stop, it will take me out into the middle of the intersection. Both feet are on the brake. I have driven for over 40 years, and this the strangest thing I have ever experienced.

- Bloomington, IN, USA

problem #198

Jan 102010


  • 8,000 miles
My 2010 Toyota Prius loses braking ability and lunges forward while braking on any uneven surface I.e. pothole, manhole cover, bump metal plate or strip, etc... this has lead to several near miss collisions and due to the amount of time I spend in the car happens an average of 3 times per day. Because I fear for my own safety I do not allow passengers in my car and I will not let anyone else drive my car. I've had to adjust my driving to try and compensate for no braking ability at any given time. I have now reported this problem to my dealer Toyota of merrillville in person 3 times and over the phone on several occasions and each time I was told they were unable to duplicate the problem and therefore there was no fix they could offer. They also tell me that I am the only customer reporting this type of concern but I have been able to connect with many Prius owners experiencing this loss of braking while over uneven pavement. I believe Toyota is downplaying this problem at the risk of public safety.

- Crown Point, IN, USA

problem #197

Jun 142010


  • 1,000 miles
I have a 2010 Toyota Prius that has the problem with the brakes sometimes dis-engaging when the car goes over uneven or slippery surfaces. Toyota was unable to fix this problem after I brought it in for the recall. The problem remains so I am stuck driving an unsafe car.

- Philadelphia, PA, USA

problem #196

Jun 032010


  • 9,872 miles
Today at yet another check for my 2010 Prius to try to discover the cause for the continual surging, I was informed that 160 times in the last 1 1/2 months I have driven with both the gas and brake pedals depressed simultaneously. This is a ridiculous assertion and completely false. Obviously there is an issue with the computer software in my Prius brakes. This is further evidence that there is a serious safety issue with the Prius brakes.

- Colorado Springs, CO, USA

problem #195

Apr 142010


  • 8,400 miles


2010 Prius engine accelerates when braking over bumps/gravel. Brought car back to Toyota dealer for recall modification and problem still exists, in fact, seems worse.

- Toluca Lake, CA, USA

problem #194

Sep 252009


  • miles
I have a 2010 Toyota Prius purchased in July 2009. During ownership I experienced when there was a crease, hole or bump in the road when braking - it accelerating and lunges. I avoided situations like that and when the recall came, I took it to butler Toyota (also had the floor mat hooks installed prior), on April 5, 2010. They supposedly fixed it. About a week later, I came upon a manhole cover in a road while braking and making a turn so going slow, and the same thing happened. The next day I purposely went through it to "test" and it did the same thing but lunge into the other lane. I was scared and called butler Toyota. They told me to call national Toyota to report. They contact butler and I went back in May 21, they did not repair it and "shrugged" their shoulders saying it's the ABS. They offered to have a field tech person come drive my car. I called national again and they seem to be "mediating" this with butler. I found a report from that this very similar issue was occurring back in 2008 and they called it "traction control". no one from Toyota has told me this. I want it fixed or a different car. I have a teenage with a permit and if he was driving this and it occurred, he would probably run into someone because it takes you by surprise. I do fear him driving it due to his inexperience and I frankly am concerned and am very cautious as a result.

- Carmel, IN, USA

problem #193

May 232010


  • 7,195 miles
At about 7:45 am Sunday May 23, I was driving West on hamburg turnpike in wayne, gently accelerating to get better mileage, the light at berdan ave and hamburg had just turned green, so I accelerated slowly to about 40 mph. At this point, I hear a shrieking beep and the car lurches forward as the brakes were applied. The dash lights up with the usual message square and the word brake! in the box. I look in all directions and saw nothing until I bounced over the construction plates. The box was gone, and the car resumed normal operation. I was puzzled. I thought it could be the plates. I checked with my son and he reminded me that in the model 5 we have radar crash avoidance. Upon further review I wanted more information. I took my son, and a camera, and drove the route again. Eureka! in all three attempts, the brakes were applied. I have pictures of the dash, and the plates. Did the car perform correctly? the second plate is not flush to the road and sticks out to the left. I think other drivers need to be aware of this possibility so they do not panic when it happens. The crash avoidance system could have been doing its job correctly. I contacted wayne police about the incident and the dispatcher said after consultation it is a county road, call the passaic county road department. My car computer will have recorded all 3 incidents. The third was not as big a jolt because the driver ahead of me had slowed considerably when he saw the plates. There is a warning sign that is beyond the plates in the picture. Let me know if anyone in service is interested in the information since this is a new feature and I know as a computer programmer of some 40+ years that a system does not always get tested for all possible events. I also cannot believe that unlike nyc where there must be no bumps or raised plates during construction that passaic county allows these plates to be installed without being flat or asphalted around the edge.

- Wayne, NJ, USA

problem #192

Apr 182010


  • 17,966 miles
After taking my 2010 Prius in for the recall fix on April 1, 2010, the vehicle continued to exhibit safety defects. I reported this to the dealer who reported it to corporate and arranged for a field tech to analyze the vehicle on April 13th. They said we would hear from Toyota with in two weeks I never heard back from the dealer so I called the dealer last week. Dealer had not heard back. I filed under the lemon law. Then dealer informed me yesterday 5/17 that the car was healthy and there is nothing more they can do. My car experienced the same brake failure this morning, turning into a parking lot.

- San Clemente, CA, USA

problem #191

Apr 152010


  • miles
The contact owns a 2010 Toyota Prius. While driving approximately 30 mph and attempting to accelerate, the vehicle would not increase in speed. The contact continued to apply continuous, steady pressure to the accelerator until it finally began to accelerate. The contact stated the failure would occur sporadically, most often when accelerating from a complete stop. The dealer was unable to duplicate the failure and the vehicle was not repaired. The failure and current mileages were unavailable.

- Spokane, WA, USA

problem #190

May 132010


  • 11,115 miles
While driving on I-430 in West little rock yesterday, I had the cruise control set on 65 mph. As I approached slower traffic ahead, I slowed the car to 60mph using the brakes. I assumed that the cruise control on my car had automatically disengaged at this point and I let off the brakes. The cruise control then caused the car to accelerate back up to 65mph as it never disengaged by using the brakes. This was especially dangerous since it happened near the crest of a hill and caused my vehicle to no longer be at a safe following distance behind the slower car in front of me.

- Little Rock, AR, USA

problem #189

Apr 302010


  • 1,200 miles
Toyota 2010 Prius, for 5 months it has been perfectly good. Bumps or uneven roads, no problem, got the Prius computer update 2-33 months ago. April 30 - driving on road with rough surface for repaving and with sewer covers sticking above surface, and no problem for 2 miles then hit a repatched hole and the car jerked ahead quickly but my braking slowed it down immediately. The entire process took 1 second. Luckily I had good reflexes. Scary but the brake worked well. Since that incident - 1 day, car is fine.

- Montgomery Village, MD, USA

problem #188

Apr 202010


  • 7,700 miles
I made a NHTSA complaint on 1/27/10 for ABS/unintended accel incidents in my prius2010. Supposedly Toyota corrected the problem on 2/11/10. On 4/20/10 @ 12:50 pm, my Prius accelerated dangerously as I was coming to a complete stop on a slight incline. The car shot forward through a red light on a busy baltimore arterial. I was braking the car and trying to turn it to avoid hitting a concrete wall or cars in the opposite lanes. I turned very sharply, unable to brake the car; I feared it may rollover. My foot was on the brake the whole time. I hopped a curb on the median and clipped a traffic sign. I then parked the car and phoned the police. It was amazing no one got hurt or killed. Since this incident occurred after Toyota said they fixed the problem, I do not trust them or my car. I want a refund for this car, I will not drive it again:it is a death machine.

- Baltimore, MD, USA

problem #187

Apr 092010


  • 970 miles
I have a new 2010 Prius with less than 1K miles. On 4-9-10 while pulling into a parking spot I experienced a simultaneous loss of braking combined with unintended surge of acceleration. My Prius jumped the curb that was perpendicular to the parking slot and stopped as it slammed into a brick building about 8 feet beyond the curb. I utilized my safety connect button to record the time of the accident and had the vehicle towed to the dealer. I contacted Toyota customer experience center and now have a case #. I was told that someone would contact me within 2 business days. I am not at all comforted by this very scary incident. I would just like to have my 2005 Prius back as I never had any problems with it. I am seeing that my problem is not unique based on many similar problems on this NHTSA complaint site.

- Erie, PA, USA

problem #186

Apr 072010


  • 14,500 miles
2010 Prius with about 14,500 miles driving on smooth, wet, paved road 20 miles an hour on a curve. Neither foot was not on a pedal - car was coasting for several seconds as expected, slowly decelerating. In the middle of the curve, with both feet still not on either gas or brake, I felt and heard a notable surge of hard acceleration despite both feet being off the gas and brake. My wife in the passenger seat also noticed the surge. I immediately braked hard. The car slowed safely, and the unrequested acceleration seemed to stop as soon as I engaged the brake pedal. Nothing was touching the accelerator before the surge, during the surge, or when the surge ended as I braked - not a floor mat, not a stray object, not my foot. This is the first time we have experienced this exact pattern of symptoms. In the past, before the brake software recall was downloaded to our car, we had many episodes of temporary loss of braking power on bumpy roads. At least one of those prior episodes had unexplained acceleration accompany the temporary braking failure on a bumpy road. Today's incident was very different - I was not braking, and the road was not bumpy. Note that the 2010 Prius is not on the recall lists for the accelerator modifications, and that a sticky accelerator would not explain this behavior.

- Lansdale, PA, USA

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