Toyota Prius Engine and Engine Cooling Problems
Owners have filed 299 complaints with NHTSA about engine and engine cooling problems on the Toyota Prius across 17 model years. The 2004 model year has the most (89). The words owners use most often: “gas engine” (8% of reports).
- 299engine and engine cooling complaints
- —median miles at failure
- 10mention a crash
- 7mention an injury
- 3related recalls
- $1,250typical repair cost reported by owners
- 42%of reports with a speed happened at 50+ mph
What owners describe
Phrases that appear unusually often in these complaints compared with complaints about other cars.
- Gas engine: mentioned in 25 of 299 complaints (8%)
- Electric motor: mentioned in 16 of 299 complaints (5%)
- Water pump: mentioned in 15 of 299 complaints (5%)
How much does it cost to fix?
Owners who wrote down what they paid or were quoted put the typical engine and engine cooling repair on the Toyota Prius at $1,250, and half of them between $730 and $4,300.
Based on 14 NHTSA complaints about this problem alone that state a repair bill or quote (2005–2014), converted to 2026 dollars with the U.S. consumer price index. These are owners' own figures, not a quote: they include dealer quotes, and owners who file complaints often faced larger repairs, so they can run higher than typical shop prices. Prices vary by shop, region and warranty coverage. How we calculate this.
At what mileage do engine and engine cooling problems happen?
Based on 244 complaints that reported the odometer reading.
How serious are the reports?
Of 299 complaints, 10 mention a crash, 4 a fire, 7 an injury.
Toyota Prius engine and engine cooling complaints by model year
| Model year | Engine and Engine Cooling complaints | Share of that year | Median miles |
|---|---|---|---|
| 2022 Prius | 1 | 4% | — |
| 2019 Prius | 1 | 3% | 95,000 |
| 2018 Prius | 3 | 8% | 89,682 |
| 2017 Prius | 1 | 1% | 81,700 |
| 2016 Prius | 1 | 1% | 223,601 |
| 2012 Prius | 1 | 0% | 9,851 |
| 2011 Prius | 5 | 1% | 15,956 |
| 2010 Prius | 33 | 1% | 13,021 |
| 2009 Prius | 7 | 1% | 18,400 |
| 2008 Prius | 16 | 1% | 19,169 |
| 2007 Prius | 17 | 1% | 34,000 |
| 2006 Prius | 20 | 1% | 46,100 |
| 2005 Prius | 64 | 6% | 18,881 |
| 2004 Prius | 89 | 15% | 12,983 |
| 2003 Prius | 11 | 11% | 75,000 |
| 2002 Prius | 11 | 7% | 77,255 |
| 2001 Prius | 18 | 11% | 37,700 |
When owners reported it
Related recalls (3)
Engine and engine cooling:engine:engine control module (ecu/ecm):software; hybrid propulsion system
Model years: 2022
Problem: Toyota Motor Engineering & Manufacturing (Toyota) is recalling certain 2022 Prius and Prius Prime vehicles. The Engine Control Unit (ECU) software may falsely detect an error and shut down the hybrid system, causing a loss of drive power.
Risk: A loss of drive power increases the risk of a crash.
Fix: Dealers will update the ECU software, free of charge. Owner notification letters were mailed November 18, 2021. Owners may contact Toyota customer service at 1-800-331-4331. Toyota's number for this recall is 21TB07/21TA07.
Hybrid propulsion system: inverter; engine and engine cooling
Model years: 2004, 2005, 2006, 2007, 2008, 2009
Problem: Toyota is recalling certain model year 2004-2009 Prius vehicles manufactured August 6, 2003, through March 30, 2009 and FCHV-adv vehicles manufactured December 12, 2008, through September 13, 2011. During manufacturing, a scratch may have occurred inside of the electrically driven water pump at the coil wire. The coil wire may corrode at the scratched portion.
Risk: The corroded coil wire may break and the water pump could stop. The corroded coil wire could cause a short circuit between coil wires and a possible open fuse, creating a stall-like condition of the hybrid system while the vehicle is being driven. This may increase the risk of a vehicle crash.
Fix: Toyota will notify its owners, and dealers will replace the electric water pump, free of charge. The recall began on January 17, 2013. Owners may contact their Toyota dealer or the Toyota Customer Experience Center at 1-800-331-4331.
Engine and engine cooling
Model years: 2001, 2002
Problem: On certain passenger vehicles, due to improper molding of the resin body of the crankshaft position senor installed on the engine block, engine oil may penetrate the seal and enter the sensor wiring connector. The wire harness connector may not be sufficiently attached to the locking tab of the sensor wiring connector.
Risk: Engine oil inside the sensor wiring connector could cause expansion due to the heat of the engine and could deform the sensor wiring connector. The connector may become disconnected, which could cause the engine to stall while driving and not be able to be restarted increasing the risk of a crash.
Fix: Dealers will replace the crankshaft position sensor free of charge. The recall began on july 26, 2006. Owners may contact toyota at 1-800-331-4331.
What owners report
Short excerpts of recent complaints, with personal details removed. Full reports are on NHTSA.gov.
The contact owns a 2018 Toyota Prius. The contact stated that while having a routine oil change, the contact was made aware that there was no coolant in the coolant reservoir. No warning lights were illuminated. The contact was constantly adding coolant to the coolant reservoir; however, the…
The contact owns a 2018 Toyota Prius. The contact stated that while driving at an undisclosed speed, the engine constantly overheated. An unidentified warning light was flashing on the instrument panel. An independent mechanic inspected the vehicle and became aware that the coolant reservoir was…
Odometer Fraud. The contact purchased a 2011 Toyota Prius. The contact stated that while attempting to register the vehicle, it was discovered that there was a mileage discrepancy. The vehicle was a dealer sale. At the time of purchase, the mileage was 145,000 and at the time of registration, it…
The contact owns a 2019 Toyota Prius. The contact stated there was a coolant leak and the coolant level was low. There was no indication of coolant on the ground. The check engine and engine HOT warning lights were illuminated. The contact stated that the failure was related to TSB: 0135-19. The…
The contact owns a 2018 Toyota Prius. The contact stated while driving at an undisclosed speed, the check engine warning light illuminated. The vehicle was taken to the dealer where it was diagnosed with a failed heat exchanger, catalytic converter, and exhaust system. The contact was informed that…
Frequently asked questions
Do all Toyota Priuss have engine and engine cooling problems?
No. NHTSA has 299 owner complaints about engine and engine cooling for the Toyota Prius. Complaint data shows that the problem is reported, not how many of all cars sold are affected.
Was there a recall on the Toyota Prius engine and engine cooling?
Yes: 3 safety recalls list engine and engine cooling. Check your VIN on NHTSA.gov to see whether the fix was done on your car.
How much does it cost to fix engine and engine cooling problems on the Toyota Prius?
Owners report a typical cost of $1,250 (half paid between $730 and $4,300), from 14 complaints that state a repair bill or quote, in 2026 dollars.
What do owners say about engine and engine cooling problems on the Toyota Prius?
The most frequent phrase is “gas engine”, in 25 of 299 complaints, followed by “electric motor” (16).
Other Toyota Prius problems
- Exterior Lighting problems (3,505)
- Service Brakes problems (2,039)
- Electrical System problems (1,595)
- Service Brakes, Hydraulic problems (1,594)
- Vehicle Speed Control problems (1,050)
- Service Brakes, Electric problems (817)
- Engine problems (479)
- Structure problems (428)
See all Toyota Prius problems.