OBSOLETE NOTICE February 27, 2026: This bulletin is no longer applicable and is now obsolete.
full bulletin at NHTSA ↗2021 Toyota Corolla engine problems
moderate Owners of the 2021 Toyota Corolla have filed 29 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
29
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2017 Corolla | 4 |
| 2018 Corolla | 5 |
| 2019 Corolla | 23 |
| 2020 Corolla | 84 |
| 2021 Corolla (this page) | 29 |
| 2022 Corolla | 6 |
| 2023 Corolla | 5 |
1crash
What stands out
Owners have filed 29 engine complaints with NHTSA against this vehicle, but no formal recall covers the issue — the federal record reflects what manufacturers have admitted, not everything owners are reporting.
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 19, 2025: This bulletin is now obsolete. Please see T-SB-0059-25.
full bulletin at NHTSA ↗Some 2020 – 2025 model year Corolla vehicles may exhibit a vibration or rattle noise from the right-hand engine mounting insulator sub-assembly. This condition will usually go away when the engine’s Revolutions Per Minute (RPM) are above idle. This condition is typically found on vehicles in warm climates/weather. No Diagnostic Trouble Codes (DTCs) are associated with this condition. This condition does not affect the operation of the vehicle.
full bulletin at NHTSA ↗The specific condition covered by this program is for a small engine coolant leak that can occur from the flow shut-off valve that can allow coolant to drip on other parts of the vehicle. This can cause "Engine Maintenance Required" to be displayed on the instrument cluster or cause the A/C not to function normally. Although the flow shut-off valve is covered by Toyota’s New Vehicle Limited Warranty for 36 months or 36,000 miles (whichever comes first), we at Toyota care about the customers’ ownership experience. Toyota is providing coverage for repairs related to Flow Shut-off Valve Coolant Leak.
full bulletin at NHTSA ↗Some 2018 – 2021 model year Toyota vehicles equipped with an A25A-FKS, A25A-FXS, or M20A-FKS engine may exhibit a condition in which an “Engine Maintenance Required” message is displayed in the Multi-Information Display (MID). Additionally, the vehicle will exhibit DTC(s) P268111 (Engine Coolant Bypass Valve Circuit Short to Ground) and/or P268115 (Engine Coolant Bypass Valve Circuit Short to Battery or Open).
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
The failure pattern owners describe
The overwhelming complaint pattern in this cluster centers on premature engine coolant bypass valve (ECBV) failure in 2021 Corolla models between 30,000 and 65,000 miles. Owners consistently report the "Engine Maintenance Required" warning message appearing and staying on, even after reset attempts. Critically, the Check Engine light often does not illuminate, creating confusion—the warning message blocks the speedometer and fuel gauge on some vehicles, forcing drivers to guess their speed.
Diagnostic code P2681-15 (Engine Coolant Bypass Valve circuit short to battery or open) surfaces in nearly every relevant complaint. The root cause is a cracked plastic housing that leaks coolant and corrodes the electrical connector. Service advisors at Toyota dealerships have told owners this is routine work—multiple complaints note the dealership knew the diagnosis immediately without testing.
Repair costs range $500–$1,000 per owner reports. Toyota does not cover this under warranty on these vehicles. A few dealerships have performed repairs as "goodwill gestures," but most require full out-of-pocket payment. One owner reports being told to expect a second replacement within 15 months. Three isolated complaints reference an unintended acceleration event, an ECU software issue, and a stuck valve, but the coolant bypass valve failure dominates the 27-complaint cluster.
Same Toyota Corolla engine reports on nearby years: 2019 · 2020
Failure modes owners describe
Engine Coolant Bypass Valve (ECBV) Failure – Plastic Housing Crack & Coolant Leak
The plastic housing of the engine coolant bypass valve cracks and leaks coolant, often corroding the electrical connector and preventing proper electronic control of engine temperature. Owners report pulling diagnostic code P2681-15 (Engine Coolant Bypass Valve circuit short to battery or open). The valve may also stick shut.
When: 30,000–65,000 miles, typically 30k–60k; appears 1–3 years after purchase on new vehicles
Symptoms owners cite: Engine Maintenance Required warning message in instrument cluster (persistent, does not clear on reset); Check Engine Light does not always illuminate despite fault code present; Message blocks speedometer and fuel gauge on some vehicles, obscuring critical driving info; Message appears more frequently or only when air conditioning is turned on; Potential engine overheating risk; Coolant leakage (visible upon inspection); Vehicle stall or loss of power (reported in at least one case)
Codes mentioned: P2681-15, P268115
Repairs/costs cited: Dealership replacement required. Owner-reported repair costs range $500–$1,000; some owners cite $700–$900 as typical. One owner notes the part itself is inexpensive (claimed ~$80) relative to labor. Multiple owners report dealerships claim they have replaced this part many times and knew the diagnosis before testing.
Recalls/TSBs owners mention: Toyota dealerships have confirmed the issue is widespread; service advisors tell customers they see it routinely. One dealership performed repair as 'one-time goodwill gesture.' Most vehicles are reportedly out of warranty at failure; dealerships typically deny warranty coverage. No official recall issued as of complaint dates. One owner mentions an unresolved known recall on their vehicle.
Unintended Acceleration (Single Report)
One complaint alleges the vehicle accelerated unintentionally while parking, over a barrier and in reverse into another vehicle. Unclear if related to ECBV issue; narrative is sparse.
When: Mileage and timing not specified
Symptoms owners cite: Vehicle accelerated forward over barrier during parking; Vehicle accelerated backward into another vehicle on reversal
Repairs/costs cited: Vehicle was being repaired at time of complaint; no repair details given.
Engine Control Unit Software Issue (Single Report)
One 2021 Corolla at 30,000 miles displayed Check Engine light and stalled. Dealership diagnosed engine control unit (ECU) software requiring update; vehicle was repaired successfully.
When: 30,000 miles
Symptoms owners cite: Check Engine warning light illuminated; Parking Brake malfunction indicator illuminated; Lane Tracing Assist malfunction indicator illuminated; Vehicle stalled and failed to restart
Repairs/costs cited: ECU software update performed at dealership.
Recalls/TSBs owners mention: Dealership performed update repair; manufacturer not contacted by owner.
Synthesized from 29 NHTSA owner complaints — unverified consumer allegations, summarized for patterns. The verbatim filings appear below.
What owners are reporting 1 most recent
My 2021 Toyota Corolla has 43k miles at this moment and the engine coolant bypass valve went out prematurely. There should be a recall on this part because a lot of people are having issues with this part on these cars at such low millage. Thanks
Had engine trouble with your 2021 Toyota Corolla?
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 2021 Toyota Corolla?
It's a documented issue but not catastrophic. 29 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?
Based on the 29 complaints filed, engine issues most often appear around 30,000 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
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/2021/Toyota/Corolla.
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.