2011 Toyota Prius engine problems

“Coolant leak into the engine, confirmed by the Toyota servicing center. This may be a common problem with the Toyota Prius, causing early engine failure from a design defect.”

“I was driving my car at over 70 mph on a highway, no check engine, no issues, just had oil changed when check hybrid system alert came on with check engine light. I started to change lanes to get to shoulder when my car just died, completely. It died in the middle of the highway merging with another major road, so I was stuck between 2 lanes of 70mph traffic on either side. The time to react to the sudden warning to my car dying was less than 2 minutes. I quickly called 911 to ask for help and was told someone had already reported my breakdown as well because my car had died in a horribly dangerous area. I was very lucky that a state trooper came quickly and blocked off my car until it could be towed for repair. I was told that I need a new Hybrid Battery. The fact that I had no signs of failure before complete shut down makes for a very dangerous driving situation and makes me second guess ever buying a Prius again.”

“The contact owns a 2011 Toyota Prius. The contact stated that while operating the vehicle, the check engine warning light remained illuminated, the vehicle had unexpectedly shut off. Additionally, the transmission failed to shift into the intended gear. The vehicle was towed to the local dealer who replaced the catalytic converter, but the failure persisted. The vehicle was towed back to the dealer who diagnosed that the inverter was faulty and needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was offered. The contact was informed that the VIN was not included in the NHTSA Campaign Number: 14V053000 (HYBRID PROPULSION SYSTEM, ELECTRICAL SYSTEM). The contact stated that the vehicle had experienced the failure listed in the recall. The failure mileage was 117,000.”

“In 11/2024, I started experiencing intermittent noises coming from the engine compartment of my 2011 Toyota Prius. The initial sound resembled the buzzing noise generated when first starting the vehicle. Then the noise started to persist for extended periods after the vehicle was turned off. It would oscillate between buzzing for approximately 10 seconds & remaining dormant for about 1 minute, repeating this cycle. The duration of these cycles could extend for up to 20 minutes. Concurrently, I experienced several instances where the brake pedal would abruptly become stiff & difficult to press. Notably, no warning lights were illuminated on the dashboard. Recognizing these symptoms as unusual, I conducted online research and discovered that the issue could potentially stem from a malfunction in the “brake booster pump and assembly.” Given the potential for a loss of braking power and the risk of personal/public safety, I scheduled a diagnostic inspection at Toyota of Poway, Poway, CA, on 12/18/2024. It confirmed the presence of a problem with the brake booster pump and associated components. In light of this diagnosis, I made the decision to refrain from driving…”

“The contact owns a 2011 Toyota Prius. The contact stated while driving approximately 35 MPH, the contact smelled an abnormal burning odor and then heard an abnormal explosion. The contact observed black smoke coming from under the hood. The contact pulled off the road and turned the vehicle off. The contact stated no warning light was illuminated. The contact lifted the hood and saw flames coming from under the engine. The contact was able to extinguish the fire with a fire extinguisher. The contact had the vehicle towed to his residence. The contact called an independent mechanic who diagnosed the vehicle and determined that the engine needed to be replaced. The contact stated that when the engine was lifted out of the engine compartment, there was a hole in the engine block. The vehicle was repaired. The manufacturer had not been informed of the failure. The failure mileage was approximately 150,000.”

“If I make a longer trip more than 10 to 15 miles the car does fine if I drive it 2 miles down the road or across the street to a different store the car tells me to check hybrid system. I had it check and code c1391 came up and that was repaired. Once repaired picked up from shop drove across the street to gas station and it told me to check hybrid system again and went into limp mode. Once I do a reset the car will start back up and drive fine as long as it's a long trip if I go on another short trip it will do it again.”