Which parts fail
Components named in complaints (engine, cooling system, oil leaks, timing chain, exhaust).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2005 Toyota Prius owners, lightly cleaned up (personal details are redacted by NHTSA).
Car started skidding on the road, couldn't take control because car started to speed up and then rammed into the concrete barrier, spun around and ended up facing oncoming traffic. Luckily, there wasn't any car right behind me and I managed to push open the driver's side door although it wouldn't open completely and opened just enough for me to squeeze through and ran out of the car. At no time did the airbag open up at all. I was lucky that I sustained no major injury except for a badly knocking my left knee on the dash. My question to Toyota would be why the airbad didn't open! What if another car had hit mine and I wouldn't have been protected by the airbag!
This is the first car we ever owned that ate oil. We are meticulous about servicing the car as recommended every 5000 miles. At the service for 100,000 miles which we did at 99,400 miles, there was no oil on the dipstick. At 103,000 miles the alarms went off 3 times to indicate there was no oil. We put in 2 quarts and took it to the shop for a diagnostic. Googling showed many other people with the same problem - no oil leak anywhere, but no oil in the car either. Toyota apparently knows of the problem and has informed service providers but will not acknowledge this problem to the car owners. We now carry oil in the car and check every time we put in gas to make sure we also have oil. The service shop suggests a $3500+ rebuild of the engine. We can afford to check oil and add it as necessary instead of rebuilding an engine that will end up with the same issue. …
Tl* the contact owns a 2005 Toyota Prius. While washing the vehicle, the contact noticed 2-3 drops of water entering the front passenger side window. The window was closed at the time of the failure. Additionally, when the vehicle was started, the contact noticed that the instrument panel failed and would not illuminate. The contact engaged the push-to-start button with the brakes applied to shut off the vehicle, but to no avail. The contact then shifted into park and attempted to exit the vehicle when the vehicle abnormally accelerated. The contact was knocked to the ground by the driver side door and sustained minor injuries. As a result. The dealer stated that the instrument panel computer needed to be replaced. The dealer failed to perform a diagnostic to determine the cause of the electrical failure or the acceleration failure. …
I was involved in an accident with my 2005 Prius on 3/29/2006. The cause of the accident remains a mystery. I was sitting at an intersection, waiting for traffic to clear. Witnesses reported that I pulled out into the oncoming traffic, resulting in a collision with another vehicle. Due to the injuries I suffered (a minor concussion resulting in retrograde amnesia), I had no recollection of the period prior to arriving at the intersection up until the paramedics removed me from the vehicle. As such, I can't explain exactly what happened. While I have no proof of this, it seems that a possibility would be an issue with the stuck accelerator that's being reported relating to the Prius. I've been at a loss to explain why I would have pulled out in front of oncoming traffic at an intersection that I was very familiar with. …
Fire and total loss of 2005 Toyota Prius, 19,300 miles after returning from work, the vehicle was parked as usual with engine power cut in the owner's driveway. A few minutes later, smoke was noticed inside the car with flames showing from underneath the vehicle. The fire department extinguished the fire about 10 minutes after it was first noticed. The main damage is in the rear left (driver's side) of the vehicle, with the cargo compartment completely destroyed, tire completely melted, all plastic in the area melted, door blackened, the rear bench destroyed, the ceiling carpet destroyed and big heat marks on the roof of the car. The vehicle was not modified as a "plug-in hybrid" which have been reported in at least one incident of fire. The external temperature was moderate, around 70-75 degrees. Updated 06/05/09
Toyota Prius combination meter not working for 2 days when I repeatly turn it on and turn it off....then works one day then is not working now---I can't see the instrument panel and how fast I am driving and then I can not shut the car off for several minutes....very unsafe. And I just had the car serviced for a messed up battery. This is a used car that I bought to replace the 2001 Toyota Prius that was rearended in dec 2016 then the dealer sold me a junk car in April 2017 now having to fix all these problems. I will sell this car as a piece of junk to the junk yard as strap metal because that what it is. Very unsafe and the NHTSA is allowing this to happen. Started on 08/22/2017 & 08/23/2017 & 08/25/2017 I can't see the panel.
Tl* the contact owns a 2005 Toyota Prius. While driving various speeds, several unknown warning indicators began flashing and the vehicle stalled. The vehicle shifted into neutral as other unknown warning indicators illuminated. The contact coasted the vehicle to a stop and restarted the engine. The contact then drove the vehicle to an independent mechanic where it was diagnosed with inverted cooling failure. The vehicle was not repaired. The manufacturer was notified and stated that the contact would have to pay for diagnostic testing. The dealer was not contacted. The failure mileage was 223,000.
Tl* the contact owns a 2005 Toyota Prius. While driving approximately 35 MPH, the vehicle stalled and all the warning indicators illuminated. The vehicle was taken to an independent mechanic where it was diagnosed with an inverter water pump failure. The vehicle was not repaired. The manufacturer was made aware of the failure and informed the contact that the VIN was not included in NHTSA campaign number: 12V563000 (engine and engine cooling, hybrid propulsion system). The failure mileage was approximately 160,000.
Car stopped accelerating/ engine died while driving at 20-30 MPH exiting holland tunnel. Coasted, then braked to stop, pulling over to shoulder. Turned ac off. Red warning light on. Ac warning light? Pressed park button. Press power button to turn off car. Waited 5 sec and then pressed power button, keeping ac off , and resumed accelerating.
My daughter was driving the family car a 2005 Toyota Prius on a nj county road on a low traffic Sunday morning in April 2009. The car unexpectedly surged causing her to loose control, hit a telephone pole and cause property and physical damage.
NHTSA investigations
Engine stalling
Odi opened pe05-029 based on 33 reports of alleged gasoline engine stalling on the subject vehicles.the subject vehicles are gasoline/ electric hybrid vehicles that can be operated in gasoline or electric modes, or a combination of both depending on the power demand.all reports allege that the gasoline engine shut down suddenly without warning.some of the complainants reported that the vehicle continued to operate…
Engine complaints in other Prius years
Frequently asked questions
How common are engine problems on the 2005 Toyota Prius?
NHTSA has 79 complaints about the engine & cooling of the 2005 Toyota Prius, 8% of the model year's 1,051 complaints. The component named most often is engine (13 mentions).
Is there a recall for 2005 Toyota Prius engine problems?
No. NHTSA lists no engine & cooling recall for the 2005 Toyota Prius, though it has 6 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2005 Toyota Prius engine problems start?
Half of the complaints with a recorded mileage happened before about 34,000 miles, and 45% before 25,000 miles.
Is it dangerous?
Owners linked 3 crashes, 1 fire and 4 injuries to engine & cooling 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.