2021 Honda Accord Hybrid Engine Problems

My vehicle is currently suffering a failed head gasket. I was alerted about this issue from local mechanics and friends way before it actually happened. I took it to services and regular maintenance even more frequently after that. However, it still failed no matter what. I took it to the dealership, they even admitted that this is a known problem for this generation of vehicle. They still proceeded to ask nearly $7000 to fix it, saying that even though this is a known issue, there was no recalls on the vehicles so they could not waive or deduct the fees.

NHTSA ID

11721881

Incident

Feb 26, 2026

I purchased my vehicle in March 25th 2024 a message on my dashboard saying engine is too hot so in August of this year I took it to the shop for a diagnosis test and they told me that the car didn’t run hot when they drove it so again in October 10th I was driving home and my car lost power on the freeway so I pulled over and then all my lights on the dashboard came on so I took it to the shop on October 13th and they told me that my head gasket was faulty and my coolant system was faulty. To me a major problem should have not happened within a years time and I had my maintenance done on my car like I should have.

NHTSA ID

11696661

Incident

Oct 10, 2025

On 3 occasions, was accelerating on interstate (after entering from ramp), check engine light began blinking, car shook terribly & went into limp mode - gas pedal was to the floor but car continued to lose power. Had to pull off road - turned car off, waited 20 minutes, turned car back on - check engine light went off & car was drivable. Another time, while accelerating on interstate, check engine light started blinking & all warning lights came on flashing. Car began losing power - had to pull off on side of the interstate - car was towed to the dealership. Another time, was pulling off from a light on highway - I accelerated, check engine light began blinking, car shook terribly & went into limp mode, requiring me to pull off on side of the highway - turned the car off for 15 minutes - turned it back on, light was off & was able to drive car. Most recent incident - was accelerating on small, 2 lane highway - check engine light began flashing & car shook terribly but didn't go into limp mode - otherwise behaved as before. Each time, took the car to the dealer ASAP to report problem. First time, was told they had to fix broken tail light b/c it was throwing off system & they couldn't get a computer reading. Once done, was told that they got a "CYL2 Miss Fire Code. Performed diagnosis on code. Diagnosis led to improperly adjusted valves. Performed valve adjustment. Found half of valves loose and half tight." Was road tested - no further concerns noted by dealer. Other times, was told that computer wasn't showing any codes. Last event literally happened in front of Advance Auto - pulled in/hooked up to check code - indicated a Cyl 2 misfire. Took to dealer - said no code showing - berated me for having checked @ Advance - said it erased any codes, even though I told them the code that was noted. This is a serious safety issue due to car going limp when accelerating on interstate where others are going 70-90 mph. Dealer says nothing they can do d/t no code showing.

NHTSA ID

11651437

Incident

Feb 17, 2024

@ 96,970 miles, (2021 Honda Accord Hybrid) when getting on the freeway and accelerating to catch up with traffic, the car began sputtering, the check engine light flashed, the accelerator stopped working and I had to get it to the shoulder of the freeway immediately. The car sputtered and shook. I turned the car off, let it sit. I tried re-starting it and it started fine, no check engine light. I drove it slow off the freeway and to my home close by. I got it to the dealer. The Service Rep said he had never heard of this issue although it does appear on Honda Forums. He said no codes showed and decided it needed a Cylinder adjustment and then decided it also needed a new (refurbished) transmission. It was in the shop for weeks. I've tried warming the car up longer and using more expensive gas. Issue continues to happen. I called an made an appointment at the dealer for first available date. Today I had it checked for codes again from a different mechanic and the mechanic said it has no codes - at all. Fluids all perfect, no issues with coolant levels. All maintenance has been completed on schedule. I did video tape my dash when it happened Wednesday, on I80, 3/5/25 12:12pm.

NHTSA ID

11646979

Incident

Oct 16, 2024

The contact owns a 2021 Honda Accord. The contact stated while driving at an undisclosed speed, the accelerator pedal was depressed; however, the vehicle failed to accelerate as intended. In addition, the check engine warning light illuminated. The vehicle was taken to the dealer; however, the failure was not duplicated. The vehicle was not diagnosed or repaired by an independent mechanic or the dealer. The contact stated that the vehicle was taken to the dealer several times due to the failure. The manufacturer was not made aware of the failure. The failure mileage was approximately 28,000.

NHTSA ID

11641072

Incident

Feb 6, 2023

Mileage

28,000 mi

Twice while driving at highway speeds the check engine light came on. My car's engine was misfiring, and I have no acceleration. Both times, I took local roads home on which I could drive below 35 mph. Pulling out from traffic lights and stop signs was difficult. The dealership where I bought the car has been unable to diagnose the problem. No codes come up on the computer, and my car is currently at the dealership. The service manager has been able to duplicate the problem and still no diagnostic codes were recorded. The dealership technicians have contacted Honda engineering for advice.

NHTSA ID

11629132

Incident

Nov 24, 2024

My car has 79700 miles and starter shaking vigorously while on the freeway. Took it to the Honda dealership and I have a blown headgasket. After reading the [XXX] forums this is a ridiculously common problem with these cars around 45-90k miles. Honda is saying it's not under warranty and it's a $5400 fix for me. With so many cars with the same 10th generation engine having blown head gaskets below 100k miles this is an problem and a safety issue. Honda needs to fix these issues for their consumers. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11619138

Incident

Oct 10, 2024

The contact owns a 2021 Honda Accord Hybrid. The contact stated while driving at an undisclosed speed with the cruise control activated, the vehicle inadvertently lost motive power. The contact was able to pull to the shoulder of the roadway, where the vehicle was able to be restarted. After restarting the vehicle, the vehicle returned to normal functionality, but the failure became a recurring failure. The check engine warning light was illuminated. The vehicle was taken to the dealer, who was unable to duplicate the failure. The vehicle was not repaired. The manufacturer was notified of the failure but provided no assistance. The failure mileage was 40,000. The VIN was not available.

NHTSA ID

11587647

Incident

May 8, 2024

Mileage

40,000 mi

2021 Accord Hybrid Touring 2.0L with 51k miles. On 10/22/2023 the check engine light started flashing so I pulled over and noticed the engine was running rough so I shut it off. When I restarted it all was fine, no CEL, so I drove it to the dealership. They stated that there are no CEL codes found, so come pick it up. I told them that the CEL flashing was a major problem and I pulled a P0304 code. 2 days later they called and told me it had blow head gasket.

NHTSA ID

11548258

Incident

Sep 22, 2023

On 4 separate occasions, the first on December 22, 2022, my Accord began losing power and acceleration while driving on the highway. The engine light began flashing but never came on steadily, and no message displayed. On a couple of occasions it was raining a bit, and at other times the weather was dry. Each time, I pulled the car over to the side of the road; before turning off the engine, I noticed the engine was loud and the car was shaking a bit. After a minute, I turned the car on and it operated normally, with no flashing engine light. I brought the car to a local Honda dealership after the first incident, but they were unable to locate any codes to make a repair. I am reluctant to use the car in any congested highway area such as New York or Boston (both I visit regularly to see family) because of losing power on a busy highway, so it is a safety issue that affects the use of my car, which is less than two years old with approximately 33,000 miles of use. After 3 more incidents, I brought the car back to the dealership today (and it happened on the way to the dealership, as well). I told the dealer that I found a reference on the internet to a Honda repair bulletin, A21-O52, that described the exact problem my car is experiencing. The dealership just told me that the repair bulletin does not apply to my car as my car is a Hybrid. They want to keep the car to keep driving it and replicate the problem.

NHTSA ID

11502798

Incident

Jan 20, 2023