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really awful
Crashes / Fires:
1 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
8,094 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 1 of 2)

problem #29

Nov 082006


  • miles


Prius stalled when pulling into traffic from a stop light. All lights on the dash board were illuminated including the check engine light. Only electric drive systems was operational. I immediately pulled into a parking lot and turned the car off. Upon restart, only the check engine light was on. Was able to drive to the dealership 2 miles away. Stored error code P0A7A was identified - bulletin EG029-05. "false M.I.L. "on" condition. An updated control ECU was installed, covered by warranty.

- San Mateo, CA, USA

problem #28

Mar 142005


  • 3,843 miles
2004 Toyota Prius engine stalled while driving. ** answer required*** the consumer requested reimbursement for the towing expense.

- Pompano Beach, FL, USA

problem #27

Sep 082005

Prius 4-cyl

  • Automatic transmission
  • 12,000 miles
I own a 2004 Toyota Prius purchased on March 2nd 2004. Approximately 4 months after acquiring my vehicle I was merging onto the interstate when I experienced and ice engine failure. All the warning lights came on and I was able to pull to the shoulder of the road using the electric motor. Subsequently I rebooted the car and the engine turned over. The next day I took the Prius to a Toyota dealership. They had the car for six days and apparently performed diagnostics and performed a software fix. Recently, on September 8th 2005 I experienced a 2nd occurrence of the ice engine shutdown. This scenario occurred while pulling up to a red light. Again all the warning lights came on and the engine shut down. I rebooted the car and took it to the dealership for service. The Toyota dealership completed a tsb EG047-04 for recalibrating the engine ECU. Note, I did not receive any prior tsb's from Toyota regarding the engine problem.

- Mechanicsburg, PA, USA

problem #26

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

problem #25

Aug 232005

Prius 4-cyl

  • Automatic transmission
  • 25,200 miles
Nothing special or extraordinary led up to this failure. I was driving to work at about 7:00am. The temperature outside was about 70 degrees and the car is kept in a garage every evening. In the middle of acceleration (I was going about 25mph), the car stalled and the "red triangle of death" came up on the dash, along with several warning lights. The navigation system also provided the word "problem" and a little, red car symbol with an exclamation point in the middle of it when this happened. I was able to drive to an apartment complex under battery power only. I then shut the car off, waited a few seconds, and then started it again. The engine did kick back in after this, but the warning symbol (little, red car) on the navigation system didn't go away. I took the car to my Toyota dealership and they said that they had to "recalibrate the engine computer." The car is now running as normal. The car is a 2004 Toyota Prius. My worry with this is what if this would have happened while driving across Kansas, while 80 miles away from anyone to help you? the battery power surely wouldn't be enough to get you to safety. This is a problem inherent in the software of the engine computer and it should be fixed for all owners.

- Indianapolis, IN, USA

problem #24

Feb 152005

Prius 4-cyl

  • Automatic transmission
  • 20,000 miles
1) my wife was driving our 2004 Toyota Prius and the car had a warning light turn on on display, went to "limp" mode (slow) and suddenly stopped after 1/2 mile. 2) car could not be controlled, no power. 3) Toyota towed car to shop and replaced ECU controller in area of fuel tank, ECU relay and entire fuel tank assembly. Problem has not happened again.

- Setauket, NY, USA

problem #23

Jul 022005

Prius 4-cyl

  • Automatic transmission
  • 23,176 miles


For the second time my 2004 Prius has stalled while driving and shut down. I have attached my previous report to you when it happed in May 2005. The first time the ECU was reprogramed. This time I was driving on the freeway going 65 miles per hour on July 2, 2005 when the emergency engine lights came on on the dash board. The vehicle quickly loss power before the engine shut down. The battery meter confirmed the loss of reserve. I had the vehicle towed approximately 50 miles to maita Toyota where I have my Prius service. The vehicle was keep from July 2 - 12, 2005. The service department was not able to identify the problem. I picked up the vehicle and drove it home today. Now I have to watch for the next time that it happens for Toyota to research the problem more. A file was open with Toyota #2005 00071145 but without any help to identify the problem. Contact 1-888-dash-2-dot (1-888-327-4236) tty â 1-800-424-9153 or â 1-202-484-5238 ÿ ÿ ÿ consumer information name : Mr. Christopher smith org. Name : address : P O box 1543 city, state, zip : carmichael, ca 95608 usa daytime phone : 9163908494 description : 5/6/05 my 2004 Prius with 20,400 miles without warning loss all power and shut down while driving hazard light came on warning to take to Toyota dealer. The vehicle would not start. The battery meter level was completely dead. The vehicle had to be towed to maita Toyota 2500 auburn blvd, sacramento, ca 95821, 916 481-5353 for repair. The work order stated the cause was the ECU which was reprogramed which cleared stored codes. Code pulled P3191. Is this a new finding in the Prius? incident date : 5/5/05

- Carmichael, CA, USA

problem #22

Jun 212005


  • Automatic transmission
  • miles
Vehicle stalled intermittently and lost power. The consumer sold the vehicle back to the dealership.

- Greenwich, CT, USA

problem #21

Jun 302005


  • miles
2004 Toyota Prius. Stalled while driving at about 40 mph. Able to restart car after driving with electric motor for a few blocks.

- Stockton, CA, USA

problem #20

Oct 122004


  • miles
2004 Toyota Prius cut off while consumer was driving at highway speeds. When the consumers vehicle stalled on the highway, another motorist rear ended the consumers vehicle.

- Boca Raton, FL, USA

problem #19

Jun 232005

Prius 4-cyl

  • Automatic transmission
  • miles


While driving around town and some highway, intermittently, the battery charge level will drop very low (one red bar), the battery will not charge, and the car will loose power. When the Prius has power loss, the average mpg drops from the low 40's to the low 30's. the car has never stalled as per current investigation with '04 Prius, but, the loss of power almost caused an accident. I have taken the car to a Toyota dealer 3 times, they are unable to find anything wrong with the car. Have also contacted Toyota Corp and escalated, but, they maintain that there is not a problem. All sofware technical bulitens and any recalls have all been applied

- Carrollton, TX, USA

problem #18

May 132004


  • 2,235 miles
Toyota Prius gas engine stalled 3 times, twice while driving on highway and on ramp. 1) May 13 2004 stalled in busy intersection going about 40 mph, electrical engine still worked, so speed dropped to 20 mph, and consumer stopped on the side. All warning lights were on. Vehicle was towed to Toyota, and they said nothing was wrong except dirty gas. They reset warning lights, and told it was safe. 2) June 1, 2004, while merging onto a highway going up the ramp at about 50 mph car jerked and slowed to about 25 mph without warning. Car behind M had to go onto shoulder to avoid rear ending consumer's vehicle. All warning lights were on again. When checking engine display only electrical power was working again. Gas engine had stalled, causing the immediate decrease in speed, without brake lights so car behind didn't know what was happening. Towed to Toyota. They said nothing was wrong again except dirty gas. Consumer changed gas stations and used their recommended ones since the last incident. Consumer refused to take the car back. Had two toddlers who were in the car at the time of the incidents. GMC dealer sent a patch which wa ssuppose to fix the problem, but patch did, T work. Problem recurred.

- Los Altos, CA, USA

problem #17

Jan 082005

Prius 4-cyl

  • Automatic transmission
  • 2,000 miles
PE05029 2 times the car engine stopped for no reason at all. Dashboard lit up entirely. Both times the car restarted. Each time, fewer lights came on. Brought car in 2X- 1st time, did nothing. 2nd time, supposedly upgraded program. When 1st heard about your investigation, contacted Toyota to see if we were part of the 33-- we believe it is being under-reported. Contact name: Diane romanchick and paul embree.

- Tustin, CA, USA

problem #16

Jun 052005

Prius 4-cyl

  • miles
2004 Toyota Prius, stalled while driving. This is the second time I have taken it to the shop for this problem.

- Corte Madera, CA, USA

problem #15

Sep 122004

Prius 4-cyl

  • Automatic transmission
  • 11,875 miles
2004 Toyota Prius, consumer was driving on highway 24 and the vehicle stopped. It had to be towed. Vehicle lost power while going 60-65 mph.. the vehicle stall again on August 29th, 2005 while being driven driving 40 mph. The mileage was 24480. The consumer contact GM and demanded a new vehicle. The manufacturer bought the consumer's vehicle back.

- Colorado Springs, CO, USA

problem #14

May 102005

Prius 4-cyl

  • Automatic transmission
  • 10,500 miles
Driving down the road at approx 45 mph in my '04 Toyota Prius. The vehicle lost power and stalled in the middle of the road. Engine stopped running and battery power ran out causing the vehicle to stall.

- Verona, WI, USA

problem #13

Sep 022004

Prius Diesel

  • Automatic transmission
  • miles
The contact owns a 2004 Toyota Prius. This vehicle would stall at high speeds. He was going 65-70 mph at time of incident. This happened without warning. It exactly what the reports said happened to him. He can be contacted by ODI for this if needed. Also, had premature wear on tires. Had the front and rear ends aligned three times since he purchased the vehicle.

- New Gloucester, ME, USA

problem #12

Jun 012005

Prius 4-cyl

  • Automatic transmission
  • 10,254 miles
I was driving on highway 101 North in a stop-and-go traffic. I noticed that the battery level continued to drop and the gas engine failed to start to recharge the battery. I manage to slide out of the freeway and stopped on the shoulder. I could not shut off the car for about 2 minutes. I was able to restart the car after 5 minutes and the gas engine started. The display showed symbols of "check engine" and "hybrid system warning" and a text message - "problem!". I was able to drive to the destination via a local route.

- Palo Alto, CA, USA

problem #11

Feb 022005


  • Automatic transmission
  • miles
I was driving my 2004 Toyota Prius at approximately 35 mph when it suddenly stalled and the electric engine power dropped to zero. I could not get the vehicle to move and needed to have it towed to the dealer for service.

- Longmeadow, MA, USA

problem #10

May 242005

Prius 4-cyl

  • Automatic transmission
  • 16,500 miles
While driving at 25mph, 4 trouble lights lit up on dashboard. After 1-2 more miles, the engine lost all power, despite the gas engine still running. The electric system showed no battery power. Restarting the engine didn't help, and the car had to be towed.

- N. Andover, MA, USA

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