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really awful
Crashes / Fires:
10 / 0
Injuries / Deaths:
9 / 0
Average Mileage:
47,949 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.

2004 Toyota Prius engine problems

engine problem

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2004 Toyota Prius Owner Comments (Page 2 of 3)

« Read the previous 20 complaints

problem #26

Oct 052007


  • miles


The contact owns a 2004 Toyota Prius. While the contact was driving 12 mph she was hit by another vehicle damaging the brake line which caused the contacts vehicle to contunially move after the crash. In order to stop the vehicle the contact had to engage the emergency brake. The contact called the manufacturer and was informed that the vehicle was difficult to stop due to the damaged brake line. The failure and current mileages were not available.

- Kenton, OH, USA

problem #25

Sep 152004


  • 15,000 miles
Information redacted pursuant to the Freedom Of Information Act (FOIA), 5 U.S.C. 552(B)(6). My 2004 Prius almost killed us in 2004. It accelerated so fast, that I had to go in the median. We could not sow it down or stop it, there was a bridge ahead, so I managed to get back on the highway shoulder and take it out of gear and slow it down. Since then has blamed eveyrthing on me, I fell asleep, etc. I did not know until know that it was the car that caused it. We could have been killed! she insisted we get rid of the car, I sold it to carmax in las vegas, where we lived. [xxx]

- Salt Lake City, UT, USA

problem #24

Jan 042008


  • 100,000 miles
The contact owns a 2004 Toyota Prius. While driving in clear, normal road conditions at speeds of 50 mph, the contact attempted to accelerate into the flow of traffic. She then applied the brake pedal, however the vehicle did not decrease in speed. The brakes would not engage and the rear of the vehicle spun out of control or fish tailed. The contact could not maintain control of the vehicle and crashed into a guard rail and a nearby tree. The vehicle was destroyed. The VIN was not available at the time of the complaint. The current and failure mileages were 100,000. Updated evoq. 05/27/10

- Mequon, WI, USA

problem #23

Mar 042010

(reported on)


  • miles


2004 Toyota Prius with brake problems. Consumer states that when applying the brakes the vehicle skids out of control.

- Beverly Hills, CA, USA

problem #22

Nov 072009


  • 64,020 miles
2004 Prius: After driving at 10mph on gravel road with potholes and then turning on to smooth paved road engine speed and speedometer started to vary wildly with speedometer going up to 45mph down and back up again for a 5 minute period while driving on the paved road at about 30mph. This continued but car itself did not accelerate abnormally despite change in engine speed and wild speedometer.

- Chapel Hill, NC, USA

problem #21

Oct 192009


  • 50,000 miles
I have a 2004 Toyota Prius. On October 19, 2009, the car accelerated by itself to 65 mph. I was able to press on the brake, slow down the car and pull to the side of the road. I had the car tolled to the local dealership and they said they could not "duplicate the problem." They told me to take the floor mat out. In the meantime, they charged me $1400 to replace a water pump and perform other maintenance services. The recent acceleration recall by Toyota does not include my car although I had the acceleration problem with this car. When I called the company to inquire the reason for this, they told me that this model was made in Japan with a different part manufacture, thus it is not under the acceleration recall, just the floor mat recall.

- Columbia, MD, USA

problem #20

May 282006


  • miles


May 29, 2006 - I was pulling into a school parking space when the Prius accelerated on its own, and although I hit the brakes, the engine started to roar, and the car jumped a concrete parking lot curb, went into a drainage swale, and stopped only when it hit an iron fence around the school where I worked. I took it to Toyota to be fixed. Told them what happened. They put it down as "car jumped curb." I wrote to Toyota on October 11, 2009, describing the incident and enclosing documentation for the repairs. They said they were sorry about the incident "however, as we were not provided the opportunity to inspect your vehicle at the time of the incident, we have no way of addressing your specific claim and are unable to offer further assistance to you in this matter." Toyota wanted me to have them inspect my car for a problem that they didn't know existed.

- Peoria, AZ, USA

problem #19

Jan 012010


  • 103,690 miles
The contact owns a 2004 Toyota Prius. While at a complete stop, the rpms suddenly increased and the vehicle attempted to move forward while the contact's foot was on the brake pedal. The dealer was contacted and he was awaiting a response. No repairs were made to date. The failure and current mileages were 103,690.

- Los Angeles, CA, USA

problem #18

Jan 242010

Prius 4-cyl

  • Automatic transmission
  • 52,000 miles
The contact owns a 2004 Toyota pruis. The contact stated that while driving he attempted to slow down by applying the brake, but the vehicle accelerated on its own. The dealer was contacted and they advised the contact to bring the vehicle in to have it diagnosed. The dealer stated that there was nothing wrong with the vehicle and they could not duplicate the failure. The contact believes that there is something wrong with the braking system. There have been no repairs to the vehicle. The vehicle is at the dealer. The contact does not want to pick the vehicle up due to the safety risk. The failure and current mileage was 52000. Updated 03/04/10 updated 07/23/10

- Doylestown, PA, USA

problem #17

May 202009


  • 42,000 miles
Twice my Toyota Prius has "surged" unexpectedly. I was coasting into a parking space both times, so was able to stomp on the brake and stop the car. When the first recall was issued I knew it wasn't the floor mat. Mine was the original one and was firmly attached. It did not move and "entrap" the pedal and I did not have my foot on the gas when the surges happened. I did not bother to report it at the time, as I am an older female and have been treated like an idiot at the dealership when I spoke with the service people. The car has been fine in every other way. I believe this is a throttle or computer/electronic problem and I believe that they know it.

- Ashland, MA, USA

problem #16

Nov 012009

Prius 4-cyl

  • 68,000 miles


About 40% of the time, my Toyota Prius doesn't want to stop or slow down when the brakes are applied. Under these conditions, I have to apply the brakes hard and then the car will slow down. It feels like the car wants to "run away" when the brakes are applied. It exhibits this behavior in many circumstances: Stopping at a stop light, slowing down on an expressway, or slowing down on a city street. Updated 11/23/09 the check engine light illuminated. The passenger front window switch wasn't opening or closing the window unless the master switch was used. The throttle body had to be cleaned. The fan belt and brake light switch were replaced. Updated 11/24/09 updated 01/06/10 updated 01/07/10.

- Miami Beach, FL, USA

problem #15

Apr 052005


  • 80,000 miles
The contact owns a 2004 Toyota Prius. While entering an interstate highway during traffic, the vehicle accelerated without intention. She shifted the vehicle into neutral and coasted to the side of the road. The vehicle was then taken to the dealer for inspection. A technician concluded that the floor-mat was the cause of the failure. However when the failure occurred she noticed that the floor-mat did not interfere with the accelerator pedal. The failure mileage was unknown. The current mileage was 80,000.

- Welches, OR, USA

problem #14

Nov 202007


  • 62,000 miles
The contact owns a 2004 Toyota Prius. When he applied pressure on the brake pedal at 50 mph in the dark, the vehicle would not stop. The anti-lock brake system activated, but the vehicle did not stop. Consequently the vehicle crashed into a tree. The vehicle was completely destroyed. He sustained injuries. The failure mileage was 62000. The vehicle identification number was unavailable.

- Patomic, MD, USA

problem #13

Apr 012008

Prius 4-cyl

  • Automatic transmission
  • 62,409 miles
I was driving on the 605 freeway in the carpool lane at approximately 70 miles per hour when without warning, the car suddenly lost power and the check engine and master hybrid warning lights came on. I had to cross four lanes of rush hour traffic to pull to the right side of the freeway as the car lost power. I was barely able to drive the car safely to the right shoulder of the freeway. The car was towed to the dealer since it was not drivable. This was a very dangerous and scary experience. Fortunately, a serious accident was narrowly avoided. The dealer attributed the problem to a short. The hybrid vehicle control computer was replaced. The replacement part number is 89981-47270.

- Torrance, CA, USA

problem #12

Oct 182007


  • miles
2nd occurrence of Toyota Prius acceleration. While wife leaving daughters school, car accelerated (pedal off the accelerator!), she jammed on brakes, but was close in provoking an accident on main street. This is the second occurrence. First time, she hit a taxi while stopped in a red light. Accident was reported by police (no injuries). First time took car into the dealer (no apparent problems). Planning on taking car again to dealer tomorrow.!

- San Juan, PR, USA

problem #11

Sep 022006

Prius 4-cyl

  • Automatic transmission
  • 16,997 miles
I turned left into driveway of a home- driveway has an incline. I turned off power and two children exited car. One passenger returned within five min and sat in front. I placed foot on brake. Brake felt "locked" with no give. I pressed power button with foot on brake, and placed gear in reverse. I let foot off brake to roll slowly out of driveway. When I attempted to brake to slow exit, my foot went all the way to floor--no power. I notice gear was neutral. Power would not turn off. Car was rolling closer toward a busy four lane street. I noticed the power button light color was red, and the following yellow warning indicators were lit: Brake system warning light, malfunction indicator lamp, anti-lock brake system warning light, slip indicator light. I depressed the emergency brake to stop. I told my 14 Y/O passenger to exit the car and when she did the master warning light came on while the above lights remained lit. The brake continued to depress to the floor. I again attempted to turn off the power without success. I exited the vehicle with my smart entry key in hand and as expected loud buzzing noise came on. I then contacted Toyota roadside assistance. The reference number is 269-568-6678. I called back later to change the reference number to 269-492-2066. I had asked for police assistance for traffic control, but the police did not show. On 9/6 a.M., jim at metro Toyota service, kalamazoo, mi called & I described the above to him. At 1530 on 9/6/06, I described my experience to marvin at Toyota customer relation. The case number he provided was 200609051137. This is the second like incident with this vehicle. I did not report the first incident to the NHTSA which occurred a few months after I took possession of the then new 2004 Toyota Prius. No reason was found for the first incident, by the same dealership service. The consumer stated the vehicle accelerated on its own. Also, when the consumer applied the brakes, the pedal became soft and went down to the floor. Updated

- Portage, MI, USA

problem #10

Mar 122006

Prius 4-cyl

  • Automatic transmission
  • 12,995 miles
: the contact stated upon entering a highway at 60 mph, the vehicle accelerated rapidly. Brake pressure was applied, but the vehicle did not stop accelerating. Each time brake pressure was applied; there was a loud grinding noise. Although the cruise control was not engaged, the cruise control was manually activated in an attempt to stop the acceleration. With brake pressure applied, the contact managed to exit the freeway using the exit ramp. When the vehicle slowed, the park button option was pressed and the vehicle stopped. There was no further acceleration or grinding noise. The vehicle was towed to the dealer and is awaiting inspection of the problem. The consumer also stated, when she applied the brakes, the pedal became soft and went to the floor. Updated

- Avon, IN, USA

problem #9

Nov 112004


  • Automatic transmission
  • 3,000 miles
My wife was coasting into a parking space with her foot on the brake. The engine apparently experienced a power surge causing the car to shoot forward violently going through a fence and over a two foot retaining wall, across a driveway and crashing into another car. Whether it was the gas engine or electric drive is not clear. Our daughter who was in the front passenger seat observed that my wife's foot was on the brake the whole time. Both my wife and daughter received neck injuries requiring treatment.

- Whittier, CA, USA

problem #8

Mar 292005


  • Automatic transmission
  • miles
Vehicle stalled /died. And lost power due to throttle failure.

- Georgetown, TX, USA

problem #7

Sep 022005

Prius 4-cyl

  • Automatic transmission
  • 13,965 miles
Total breakdown of wife's 2004 Prius on September 2 in fine weather one in san jose. The vehicle displayed sudden and significant loss of power while merging into the interstate. Loss of gas/engine power with failure of the internal combustion with engine to start, resulted in only electric motor propulsion and breakdown on the highway as the battery quickly went to single pink bar level within a 1/2 miles. Multiple mil lamps lit up and stayed on. Began to merge onto the highway from a stop speed of 30 or 40 mph and slowly accelerated into heavy traffic. She had to pull off to the (ugh) breakdown lane of the highway with all of its debris, etc. The dealer completed the repair, san jose invoice number tocs190787 dtd 9/2/05 applied EG047-04 on car. The dealer repairs seemed to have fixed the car. Contacted a Toyota Prius advisor with three concerns: If there was a service bulletin for this characteristic that would prevent the roadway failure then why was it not executed during prior services 3-9-05, 5-26-05 & 6-09-05 at this same dealer. What led one to believe that the car was not reliable after this repair. The consumer, an accomplished engineer, a knew about software bugs. A software bug did not impair operation until the right combination of environmental factors was reached. The consumer assumed that all Prius had this potential bug that contaminated the electronic control unit (ECU). ECU.

- San Jose, CA, USA

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