Table 1 shows one common engine and engine cooling related problems of the 2021 Honda Accord.
| Problem Category | Number of Problems |
|---|---|
| Engine And Engine Cooling problems |
Driving on the highway, my dashboard lit up like a christmas tree. Car started having white smoke at tail pipe. Check engine lit blink 5 times. Had 4 kids under 14 years old in car. Almost got hit trying to merge over. Turns out misfire cylinder 4. Head gasket. Only 81,000 miles. I have owed 5 months. Car currently at Honda, they want almost 4,400 to repair. But apparently, Honda is aware of these head gaskets going prematurely, in 1. 5 l. And has done nothing about it. I do not have the money to repair this car on top of how dangerous it was to be driving on the highway. When this happened.
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.
I am writing to file a complaint on the service that was provided at vann york Honda. On February 17, 2026, I was returning home from work and my car had a hard idle at start up. I was able to drive it home without issue. The next day, February 18, I got in my car and I had another hard idle start with many check engine codes appearing on the dashboard. I drove it to vann york Honda in high point, north carolina for service. I was told it was a faulty fuel injector causing the problem and that it needed to be replaced. I left the car there over night and paid for the service; approximately $3,000. I got the car back on February 19. On February 20, I again had a rough idle on start up. I brought the car back to vann york Honda and advised them that I was experiencing the same issue as before. The mechanic brought it to the back and advised me that he could not find anything wrong with the vehicle and that it is running fine. I expressed my concerns with the vehicle and he stated that without a error code or check engine light being on, it would be difficult to diagnose. The technician and the advisor said to keep driving it until a light comes on saying there is a problem since they could not find an issue. In the following 2 weeks, I had regular rough idles on start up and the fuel efficiency dropped approximately 6 miles per gallon. When I filled the car with gas, the fuel range dropped from 540 to 370. When I called about that issue, they said they reset the computer when performing the previous service on the vehicle and it is taking time for the computer to "learn" the car again. On March 6, I brought the vehicle back to vann york Honda due to many check engine codes appearing on the dashboard. On the way to vann york, the service advisor called me and stated that she would be reaching out to Honda corporate to see about Honda paying for some of the cost of this service. My wife and I drove into the service bay and I spoke with the service adviso.
All the lights came on in my car and it wouldn’t accelerate. Brought to dealership and they stated it was a blown head gasket and it was a known problem with the 1. 5 turbo cars. There are also 2 others problems that are known problems with these cars and Honda isn’t doing anything about it.
I am reporting a serious safety concern involving my 2021 Honda Accord sport se. The issue began at approximately 78,000 miles when multiple warning lights suddenly appeared on the dashboard while driving. At the same time, the vehicle began shaking and had difficulty accelerating. The engine felt unstable and the car struggled to gain speed. I immediately took the vehicle to a mechanic where it was diagnosed with an engine misfire on cylinder 3. The spark plug and ignition coil were replaced. After this repair the vehicle appeared to run normally for a short time, but the exact same symptoms returned shortly afterward. The vehicle again began shaking while driving and experienced loss of power and poor acceleration. This creates a serious safety concern, especially when merging onto highways or driving in traffic where sudden loss of power could lead to an accident. After researching this issue, I discovered numerous complaints from other owners of 2021 Honda Accords describing the same symptoms that ultimately resulted in blown head gasket failures. These complaints appear in the NHTSA database and other consumer forums. The pattern of engine misfires, shaking, and loss of acceleration appears to be consistent across many vehicles with similar mileage. Despite the number of similar complaints, there are currently no recalls associated with my VIN. I believe this may indicate a broader manufacturing defect affecting these vehicles. I am requesting that NHTSA investigate this issue further to determine whether a safety defect exists that could require a recall or other corrective action.
Head gasket blew randomly. Just hit 100,000 miles. I was on the highway and my speed just started to decrease 65 to 35.
Financed a used 2021 Honda Accord sport in April of 2024 with 68,671 miles. About a month ago, with no warning signs of any sort such as overheating etc. . . My car did not want to start, finally started but was sputtering with a rough idle, my dash lit up with like 7 or more warning lights. Including a flashing check engine light. All the were safety warnings from braking system not working, to power steering to emissions failure, etc. . . And to take to dealership. Got the car to a local mechanic to get a diagnostics reading and was told I had a misfire in cylinder 2. Replaced the #2 coil and spark plug. Thought everything was fine until picking up my daughter from school and then all those warning messages lit my dash up again including the flashing check engine light. Car started sputtering and went into limp mode. Lost power and by the grace of god was able t9 coast off the major blvd away from traffic and out of harms way. Very, very scary. My life literally flashed before my eyes. Not only my life was in danger but my daughters along with other drivers around me. So I took it back to mechanic and he ran diagnostics again still had a misfire. He could not pin point the exact problem. Took it to the dealership and they confirm it was a faulty head gasket between cyl 2 and water jacket. And they quoted me a price of $5,998. Which I can not afford. And feel im not responsible for catastrophic major mechanical failure. I maintenance my car regularly thru the dealership so they have record of me properly maintenancing the car. Head gasket failure at 80,000 miles is absolutely unheard of. Until I started researching and come to find out this is a design flaw made by Honda. I was flabbergasted with the amount of people with the exact type of problem. Im afraid that even after repairing this problem that it may happen again down the line. And that would be putting my life in danger. Vehicle is still at dealership being that I can not afford the repairs.
Stretch timing chain 1. 5 t, 86000 miles. It is very common in these motors. Just had to pay $2400 to have it replaced.
Vehicle accelerated on its own and propelled the vehicle over a curb and into a building. This occured even though the gear shift was in the park position. My grandchild and I were thrown forward as vehicle hit the building. Vehicle has not been inspected since incident occurred just yesterday, 11/20/2025. No warnings preceded the incident,.
The contact's girlfriend owns a 2021 Honda Accord. The contact stated that while his girlfriend was driving at an undisclosed speed, the check engine warning light and several other unknown warning lights illuminated. Additionally, the contact stated that the engine was slightly misfiring while driving. An independent mechanic replaced the spark plugs and the ignition coils at the residence; however, the failure recurred 3 weeks later. The mechanic inspected the vehicle but could not determine the cause of the failure. The vehicle was taken to the dealer, where it was diagnosed with head gasket and fuel injector failure. The contact was provided an estimate for the repair. The vehicle was not repaired due to the cost. The manufacturer was not notified of the failure. The failure mileage was approximately 74,000.
Starts vehicle at cold start and notice right away engine turbulence, engine light flashing, lost some coolant and white smoke. Scan vehicle for codes, engine misfire #2.
Car will drive fine , then all of a sudden it shuts completely off on the highway which is a major safety concern. All the lights will pop on in the dash board without any warning. Car will act as if it doesn’t want to pick up speed then after about 10-15 mins starts driving fine . This is my second time contacting you all regarding the same issues . Honda needs to definitely do a recall ASAP this is not safe at all to be driving around like this . Alot of customers driving 2018-2022 Honda Accords have been having the same exact issues . .
I hereby state that my 2021 Honda Accord has experienced major mechanical failures involving the transmission and head gasket. The vehicle began exhibiting mechanical issues including rough shifting, loss of power, and engine overheating. Upon inspection by a qualified automotive technician, it was determined that both the transmission and head gasket have failed prematurely. These failures have rendered the vehicle unsafe and inoperable, resulting in significant repair costs, loss of use, and financial hardship. The nature and timing of these failures suggest a possible manufacturing or design defect. This statement is submitted in support of a formal claim and potential legal action against the responsible parties for the defective condition of the vehicle.
Head gasket blown I had a diagnosis ran at the Honda dealership and it came back as a blown gasket its preventing me to accelerate whole on the highway im going at high speeds and it slows down like im slmming on brakes.
Hello, I have a 2021 Honda Accord sport 2. 0t engine. The engine has a 2. 0 liter turbo. I have had to replace two fuel pumps, which were covered my extended warranty. Another issue that I had to repair, and one that has not fully been resolved is the head gasket. I have been losing coolant at an alarming rate. Every two weeks I have to fill up coolant. I had the head gasket repaired at a Honda dealership, and this is currently being diagnosed by another Honda dealership, as I do not want to deal with the Honda dealership in cedar rapids, iowa. Currently, a Honda dealership in iowa city, iowa is handling the issue, but the head gasket along with the cylinder head were originally repaired in October 2025. Since December 2025, I have been losing coolant on a regular basis. I still have 5,000 miles left on my extended warranty, but there have been many owners who have had their head gasket replaced, or are needing replacement, and Honda refuses to acknowledge that there is a manufacturing defect with the engine. The 2. 0 liter turbo engine has a major design flaw with it's cooling passages, and Honda has yet to come up with a resolution. Having an engine overheat is a major safety concern! the current dealership is driving my vehicle on a regular basis, in fact the service advisor is driving it to work and back home (35 miles each way) to replicate the problem. At this point, a recall should be issued by Honda, as there is currently a class action lawsuit that has occurred in the state of California.
The head gaskets are known to fail on the 10 generation Accord. It failed on my 2021 Honda Accord ex-l. I left work and while I was driving the dashboard lit up with every possible light. This was quickly followed by the vehicle losing power on the highway. I ultimately got it repaired by a Honda certified mechanic. The mechanic took it to a Honda dealer to confirm it was the gasket, in which it was. There were no warning lamps message or other symptoms prior to the failure. At the time of power loss I was on an 8 lane highway at 70mph. Luckily no accidents occurred, but the failure definitely put my safety at risk along with others. The mechanic I took my vehicle to has all available information if needed upon request.
My car ran hot for the first time and I was told my head gaskets were blown and I needed a new radiator. Once I got that repaired I was then told my transmission cooler went bad on my car which caused my engine to run hot and blow my gaskets in addition to cracking my radiator. I keep my car serviced as required with the Honda dealership and they had advised seeing this same issue in several other vehicles like mine. My car has less than 100k miles and I am the only owner. It has never given me any warning lights. The techs feel this is a manufacturer defect as my car should not be having this type of issue this soon. That’s the benefit of a Honda as I have owned several new Hondas and have never had any issues. I have done research and there are several forms with this same issue reported. I am attaching the initial work order. I was just advised of the transmission issue on Monday.
The contact owns a 2021 Honda Accord. The contact stated that while her son was driving at an undisclosed speed, the vehicle experienced a loss of automotive power and stalled. The vehicle was towed to the local dealer who diagnosed the vehicle and determined that the head gasket was blown. The vehicle was not repaired. The manufacturer was not yet contacted. The failure mileage was unknown.
Head gasket blown before 50k miles even at 30k miles ive seen it happen to my friend!.
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.
Note: the item / malfunction described below is currently under recall for multiple Honda models but has not yet been recalled for the 2021 Accord sport 2. 0t. Please add this model to the recall list!!! I had been driving on the interstate for about 30 minutes on Thursday, 11/7, when suddenly seven of the warning lights flashed in succession on my vehicle, including braking system warnings, emission system warnings, and tire pressure system warmings. I pulled to the side of the road, quite concerned. I called the dealership. The service professional thought it might be the radar on the front camera causing an electrical system malfunction. I was advised by the service technician to drive slowly (about 55mph) and come to the dealership (about an hour away). Upon inspection by the dealer, it was determined that the high-pressure fuel pump in the engine was defective. I did a bit of research: this is the same part that is currently under recall for 720,000 vehicles (2023–2024 Honda Accord and Accord hybrid, 2025 Honda civic sedan and civic sedan hybrid, and 2023–2025 Honda cr-v hybrid). Please add the Honda Accord sport 2. 0 t, 2019-2022 to the recall list for this issue!.
@ 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.
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).
This vehicles have a engineering flaw in the design of the head gasket failing prematurely disabling all components of vehicle at any given time wether it’s in the highway or local the car will basically shut itself down causing a major risk for the driver and civilians even death. This is a safety hazard, tragedy waiting to happen y’all should act now theirs multiple and quiet frankly the corporation should be taking care of it since they are still allowing them out on the road even with knowledge of this issue the customer should not loose their life nor money to a mass production engineering flaw that’s is over seen by NHTSA, Honda. I got in to an accident due to my vehicle not being at 100% because of the head gasket issue the cars availability to detect or use its components, mechanically or electrical.
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.
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.
Brakes failed and steering took over the car uncontrollably and went in all different directions hitting whatever it came across and ending up stopping after hitting the last thing.
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.
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.
Upon pulling into a parking space, with the steering wheel almost at full lock to the right, when I braked, the car suddenly accelerated out of control and hit another car. Airbags did not deploy but there was damage to both vehicles, no injuries. Vehicle has been taken to a collision repair shop to await repair. It is available for inspection. Has not been looked at to date.
While driving in heavy rain on interstate, vehicle experienced lack of power and flashing check engine light. Driver was unable to maintain speed. Pulled off at next exit and turned off. Roadside assistance was contacted immediately after pulling off. Vehicle restarted and ran normally after allowing it to remain off for approximately 1. 5 hr. Roadside assistance was cancelled. Continued trip without further incident.