Problems · by component
2012 Toyota Prius engine problems
71 owner complaints to NHTSA about the 2012 Toyota Prius cite engine, 10% of all 688 complaints for this model year.
Complaints
71
10% of all complaints
Crashes
1
Reported by owners
Fires
1
Reported by owners
Injuries
0
Reported by owners
What owners say about the engine
Verbatim from NHTSA complaints, newest first
“Unknown. There were a multitude of codes that appeared on the diagnostics causing problems with engine. The temperature, brake, tire sensor lights are all on. The cruise control is not working. White smoke emitting from tail pipe and engine. Main engine coolant leaking. Car overheating rapidly.”
“I am writing to express a complaint regarding the issues I have experienced with the brake system of my Toyota Prius C, 2012 model. For the past several months, I have noticed that the brakes exhibit strange noises, soft pedal sensation, reduced braking efficiency, were driving and the ABS, traction, brake, and that other light turned on and the brakes became slow these issues have been observed on multiple occasions and pose a safety risk to myself, other drivers, and pedestrians. I have taken the vehicle for inspection, but the problems persist or have not been definitively resolved. I believe these faults may be related to defects in the braking system, and therefore I request a thorough inspection and necessary repairs at no cost, considering that the manufacturer could be responsible for manufacturing defects.”
“The contact owns a 2012 Toyota Prius V. The contact stated while driving at an undisclosed speed, the temperature gauge and check engine warning lights illuminated. The vehicle then stalled. The vehicle was able to be restarted. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 190,000.”
“The contact owns a 2012 Toyota Prius. The contact stated that when the vehicle was started, there was a rattling sound coming from the vehicle. The contact stated that while depressing the accelerator pedal, the vehicle started shaking abnormally with a rattling sound. The vehicle was taken to the dealer where it was diagnosed with a blown head gasket and that the engine block needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 106,000.”
“I bought my first used car, 2012 Toyota Prius, from Fowler Toyota back at the end of October 2023, but I was not able to pick it up until September 21, 2023 due to extra time for re-conditioning. I did not haggle about the price nor complained about the 3 week delay. In the last 3 weeks of owning my car, the TPMS sensor light and check engine light infrequently turned on. February 28, 2024 all the fault sensor lights on my instrument panel are on, along with the loss of proper braking function. I was not worried about the other sensor faults, but brake malfunction is a matter of life and death to myself and others on the road. I have had the car for a little over 4 months and less than 10k miles. I brought the car in to diagnose all the error codes. The dealer said it will cost over $2600 to fix the brake malfunction. I chose this particular car because carfax had well documented service records and Fowler Toyota advertised that every used vehicle for sale has surpassed rigorous inspection. I voiced my complaint to the used car director and he offered numerous default excuses for unforeseen problems inherent in buying a used car. I said I did my due diligence…”
“I was driving on the internet doing 60mph and there was a very loud bang and then a shaking of the parts under the hood. I was right next to an exit and coasted off the exit to a hotel parking lot. I had car towed to my mechanic. He said that the piston went thru the engine and the engine is done and needs replaced. I am having a hard time trusting Toyota again to purchase another Prius. I have had Prius for over 10 years and never had anything like this occur. I had no warning signs and no dashboard lights lit up until after all of this occurred and scared the life out of me then the engine light came on.”
Showing 6 of 71 reports. Read every report on NHTSA.gov.
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 3, 2026NHTSA vehicle page
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.