This bulletin includes basic procedures for performing a rescue charge at battery on high voltage (HV) Ni-MH and Li-ion batteries.
full bulletin at NHTSA ↗2018 Toyota Prius engine problems
moderate Owners of the 2018 Toyota Prius have filed 4 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of September 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
4
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2014 Prius | 13 |
| 2016 Prius | 6 |
| 2017 Prius | 8 |
| 2018 Prius (this page) | 4 |
What stands out
Of the 13 model years of Toyota Prius we track for engine problems, this one has the fewest owner complaints on file (4).
Owners are still filing on this — the most recent NHTSA engine complaint for this vehicle was logged 29 days ago.
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
OBSOLETE NOTICE August 20, 2026: This bulletin is now obsolete. Please see T-SB-0051-26.
full bulletin at NHTSA ↗This bulletin includes basic procedures for performing a rescue charge at battery on high voltage (HV) Ni-MH and Li-ion batteries. This bulletin should be used in conjunction with the applicable model and model year Repair Manual while performing the battery rescue charge. The GRX-5100 should be used wherever the Repair Manual references the Toyota Hybrid System (THS) charger.
full bulletin at NHTSA ↗Some 2020 – 2024 Corolla HV, 2017 – 2022 Prius Prime, and 2016 – 2022 Prius vehicles equipped with a 2ZR-FXE engine may exhibit a MIL ON condition with Diagnostic Trouble Code (DTC) P210015 (Throttle Actuator "A" Control Motor Circuit Short to Battery or Open), or P210019 (Throttle Actuator "A" Control Motor Circuit Current Above Threshold), or P211172 (Throttle Actuator "A" Control System Actuator Stuck Open) present. The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic has been modified to reduce the possibility of this condition. REVISION NOTICE April 17, 2024 Rev1: •The Required Tools & Equipment section has been updated.
full bulletin at NHTSA ↗Some 2020 – 2024 Corolla HV, 2017 – 2022 Prius Prime, and 2016 – 2022 Prius vehicles equipped with a 2ZR-FXE engine may exhibit a MIL ON condition with Diagnostic Trouble Code (DTC) P210015 (Throttle Actuator "A" Control Motor Circuit Short to Battery or Open), or P210019 (Throttle Actuator "A" Control Motor Circuit Current Above Threshold), or P211172 (Throttle Actuator "A" Control System Actuator Stuck Open) present. The Engine Control Module (ECM) (SAE term: Powertrain Control Module/PCM) logic has been modified to reduce the possibility of this condition. REVISION NOTICE April 17, 2024 Rev1: •The Required Tools & Equipment section has been updated.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 3 most recent
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 following day the coolant reservoir was empty. The failure had occurred on several different occasions.…
Tl* the contact owns a 2018 Toyota prius. While driving 20 MPH, the electrical system failed and everything in the vehicle shut down. The vehicle decelerated and lost power. While the vehicle coasted, the engine restarted on its own. The vehicle was driven to Toyota vallejo (201 auto mall parkway, vallejo, ca 94591, 707-552-4545) to be diagnosed, but the failure could not be replicated. 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 empty. One month later, the same failure reoccurred. A second independent mechanic inspected the…
Had engine trouble with your 2018 Toyota Prius?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2018 Toyota Prius?
It's a documented issue but not catastrophic. 4 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Mileage data is limited for this issue. Owners report failures across a wide range, suggesting cause is more about driving conditions and maintenance than mileage alone.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2018/Toyota/Prius.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.