2021 Hyundai Sonata
Problems, recalls and owner-reported issues
Engine is the leading concern among 134 owner complaints filed for this model year. This is the 22nd highest complaint count among 26 Sonata model years with reports.
Of the 2021 reports, 7 involved a crash. 13 people were injured.
What owners report most often
Recalls and investigations
Fuel system, gasolineNov 18, 2025
Hyundai Motor America (Hyundai) is recalling certain 2020-2023 Sonata vehicles. A damaged check valve can allow air to enter the fuel tank, causing it to expand and contact hot exhaust components, melting the tank.
A melted fuel tank can leak, increasing the risk of a fire.
Dealers will inspect and replace the check valve. The fuel tank assembly will be inspected for damage and replaced if necessary. Additionally, dealers will inspect and update the engine control unit software. All repairs will be performed as necessary, free of charge. Owner notification letters were mailed beginning March 13, 2026. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 286. Vehicle Identification Numbers (VINs) involved in this recall became searchable on NHTSA.gov on November 19, 2025.
Campaign 25V796000 on NHTSA.gov
Power train, automatic transmissionOct 6, 2022
Hyundai Motor Company (Hyundai) is recalling certain 2021-2022 Santa Fe, Sonata, Veloster N, 2022 Santa Cruz, Elantra N, and Kona N vehicles. The vehicle's "fail-safe" limited-mobility drive mode may be impaired, when prompted by a transmission oil pump malfunction, which can result in a complete loss of drive power.
Loss of drive power increases the risk of a crash.
Dealers will inspect and replace the transmission, as necessary. Dealers will also update the transmission control unit software. All repairs will be performed free of charge. Owner notification letters were mailed January 10, 2023. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 236.
Campaign 22V746000 on NHTSA.gov
Visibility, windshieldDec 28, 2021
Hyundai Motor America (Hyundai) is recalling certain 2020-2021 Santa Fe, 2021 Sonata, and Elantra vehicles. During manufacturing, the windshield may not have been properly bonded to the vehicle, allowing it to detach in a crash.
A windshield that detaches from a vehicle during a crash can increase the risk of injury.
Dealers will remove and reinstall the front windshield panel, free of charge. Owner notification letters were mailed June 20, 2022. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 216.
Campaign 21V00M000 on NHTSA.gov
Fuel system, gasoline, delivery, hoses, lines/piping, and fittingsJul 9, 2021
Hyundai Motor America (Hyundai) is recalling certain 2021-2022 Santa Fe and Sonata vehicles equipped with 2.5L turbocharged engines. Fuel may leak at the pipe connection between the high-pressure fuel pump and fuel rail.
A fuel leak increases the risk of a fire.
Dealers will inspect and tighten, or replace the fuel pipe as necessary, free of charge. Owner notification letters were mailed on September 3, 2021. Owners may contact Hyundai customer service at 1-855-371-9460. Hyundai's number for this recall is 207.
Campaign 21V524000 on NHTSA.gov
Representative owner complaints
134 reports, newest first.
Electrical system, Sep 7, 2024
Blower motor on 2021 Hyundai Sonata SEL stopped working. Same issue happened on my 2020 Hyundai SEL and currently waiting on my 2020 Sonata to be fixed. Hyundai technician said the wiring harness had a crack and it’s why my 2020 Sonata’s Blower motor stopped working. It’s now three months since they diagnosed and ordered the wiring harness but supposedly it’s still on back order and I’m left with a hot car this entire summer and possibly a cold car come this winter. Now it looks like I will have the same issue with my 2021 Hyundai Sonta.
Electrical system, Sep 5, 2024
Fuse box has a defect causing the AC blower motor to intermittently not work. Appears to be the result of loose connections between the fuse box and the fuse itself. The receptacle for the fuse is clearly burnt/melting, and appears to pose as a fire hazard as a result. The car is currently in the shop for repair on this part, but won't likely be fixed for a month+. I do have photos of the damaged parts, should it be requested. The car was taken into a Hyundai dealership for repair work in November 2023, and I was told the fuse had blown but that they fixed it. I was never told about the box appearing damaged/melting at that time, or this being a common problem. It worked again till July 2024. Car was just dropped off 9/3, due to backlog of cars at dealership. The only symptom of issue was the AC blower motor would stop working at random. It would turn back on/off while driving. This seems to be due to the loose connections between fuse box and fuse.
Power train, Aug 9, 2024
Issue with DCT transmission. Unknown remedy
Other or unspecified, Aug 2, 2024
UNKNOWN Wednesday 7-3-24 I was driving on an interstate at night, going approximately 74mph and my car totally powered down and powered back on with no warnings. Everything on the dashboard and display screen went black. This was totally random and has never happened before. I’m a second owner, previously owned by a rental car corporation. I have no idea if there has been previous recalls that have not been repaired or not.
Power train, Engine, Fuel/propulsion system, Jul 19, 2024
I have been to the dealership on three separate occasions due to the engine misfiring. Two ignition coils have been replaced so far and I recently returned to the dealership for the same issue. This time however, not only did the engine light come on but I went from a full tank to less than a quarter of a tank and the engine is making backfiring sounds. At that time the dealership said that they could not recreate the issue, I got my oil changed and went home. That was a week ago, I am back at the dealership today for the same thing; fuel dumping and backfiring sounds. While at the dealership today it turns out those backfiring noises were the fuel tank expanding so much so that it kept popping the seat up. They deemed the car unsafe to drive and it is currently at the dealership.
Engine and engine cooling, May 23, 2024
The contact owns a 2021 Hyundai Sonata. The contact stated while driving 15 MPH, the contact noticed that the passenger’s side rear seat level had become elevated. The contact stated that his daughter who was seated in the child seat head had started touching the top of the sunroof. The contact became aware of a gasoline odor coming from the engine. The contact also became aware that the vehicle was consuming an abnormal amount of gasoline. There was no warning light illuminated. The vehicle was taken to the dealer however, the diagnostic test result was undisclosed. The dealer was unsure of how to service the vehicle. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 87,000. The VIN was not included.
Power train, Vehicle speed control, Apr 25, 2024
Vehicle began to lose power while on highway. The loss of power occurred for a few seconds, then came back. Shortly after, the RPM began changing uncontrollably. Tried shifting to manual control using paddle shifters and was able to maintain steady RPM until vehicle software switched back to automatic and RPM swung crazy again. Endangered other vehicles on road due to loss of power and fluctuations of transmission. Once parked, vehicle did not change to neutral, drive, reverse. Both manufacturer and insurance are/have reviewed vehicle and are working on a fix. No warning lights. Only indication was minor loss of power prior to incident. Loss of power was not considerable nor for a prolonged period of time.
Electrical system, Apr 15, 2024
Infotainment center won't switch to Radio. No signal for AM/FM or Satellite. Then HVAC system stopped blowing. No defrost, won't blow heat or AC. Blower motors been tested and works, blower motor resister replaced. Everyone I talk to is saying it's an electrical, connection issue.
Engine, Mar 22, 2024
faulty engine thermostat
Other or unspecified, Fuel/propulsion system, Mar 10, 2024, crash
WAS PARKED IN BANK PARKING LOT. STARTED ENGINE, PLACED CAR IN REVERSE AND CAR ACCELERATED AT A VERY HIGH RATE OF SPEED. (LIKE I WAS IN A DRAG RACE!!) APPLIED BRAKES, WHICH DID NOT SLOW THE VEHICLE DOWN. DID NOT STOP UNTIL I RAN INTO A PARKED CAR. WHOLE INCIDENT TOOK JUST SECONDS. CAR HAD BEEN IN FOR REGULAR SERVICE AT THE DEALERS ON [XXX]. NOW HAS 16,597 MILES ON VEHICLE. CAR TO BE SERVICED AT RACHELS COLLISION, 720 S NOVA ROAD, DAYTONA BEACH, FL ON MONDAY [XXX]. IF I HAD NOT RAN INTO A PARKED CAR, I WOULD HAVE ENTERED [XXX] IN DAYTONA BEACH SHORES, FL WHICH WAS CROWDED WITH MOTORCYCLES.... FRIDAY NOON DURING BIKE WEEK. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)
Engine, Dec 9, 2023
I was on the highway going 60 mph then all of a sudden my vehicles rpm's jumped way up to 8 and completely lost power was on I-45 in Conroe thankfully I was in the slow lane. I have attached pictures of my dash so I could get proof this time. I had to wait 7 minutes for the car to do anything. It also burned all of my engine oil. So had to buy oil for my vehicle. I just had my oil change 3 weeks ago. This has happened before on on the frontage road a few months ago. I have claims open with Hyundai Customer Care. I have been stating that my engine makes a clicking noise, it hesitates, and seizes all the time. I have had this problem since March of 2021 and I bought the car in January 2021. I know I am not a part of the engine recall but I should be. I am scared to drive it. Hyundai doesn't care one bit. Well enough is enough I will be getting rid of this death trap. If you are looking at Hyundai's don't waste your time or money.
Other or unspecified, Dec 8, 2023, crash
1. Vehicle Speed Control 2. I was in a friend's driveway with the car in drive with auto hold activated. Car lunged forward and not able to stop it. Ran into a garage door did substantial damage to home owners property. I guess we were lucky the door took the impact. 3. I took to dealer today to report and have appointment to have looked at on January 8th. They have no previous report of this happening. 4. I have contacted my insurance company, but they are just filing a claim. 5. I was talking to my guest and was not looking at the dashboard, but I saw no warning message after the fact.
Engine, Oct 23, 2023
I have a 2021 Hyundai Sonata SEL with a Smartstream 2.5L engine w/ GDI & MPI. I have have always heard a loud knocking noise coming from my engine since I got the vehicle when in park. When you are accelerating it hesitates and you can hear a knocking noise. I have taken it to the dealership multiple times and they were able to feel and hear what I was talking about but ensured me it was fine. Recently it has been a lot worse. On 10/18/2023 I was getting on to the highway from the feeder. I tried to accelerate to about 50 mph and I heard the same knocking noise and my rpms jumped all the way to the top. Then my car suddenly stopped getting on to the highway. It took it about a minute before I could start driving again. Luckily there was no one behind me because it could've been really bad. I got home and looked under the hood and it looked like oil had sprayed out of the engine. You could to see oil splatter on the fender. No one was hurt thankfully. I have been complaining about the knocking and hesitation while accelerating for almost 2yrs.
Engine, Sep 25, 2023
The contact owns a 2021 Hyundai Sonata. The contact stated while driving 45 MPH, the vehicle inadvertently lost motive power in the middle of the roadway and failed to restart. The vehicle was pushed to the shoulder of the roadway, where the failure persisted. No warning lights were illuminated. The vehicle was towed to the dealer, who determined that there was no oil in the engine, causing the engine to seize. The vehicle was then towed to another dealer, who confirmed the diagnostic results. The contact stated that an oil change was performed three days prior to the failure. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 44,000.
Power train, Sep 23, 2023
I took off from the house about 1 mile the car stop in the middle of the road with no warning, lights or anything. Thank God I didn’t get an accident we took the car to the dealer and the dealer telling us it’s not covered by warranty. This is 2021 Hyundai sonata lease with only 44,000 miles my wife is so scared to driving Hyundai anymore. We talk to the dealer they don’t give us loaner car still one week from now they are telling us to pay $13,000 for the repair.
Other or unspecified, Sep 2, 2023
The car slowly goes forward after releasing the break
Power train, Aug 16, 2023
The contact owns a 2021 Hyundai Sonata. The contact stated while driving at an undisclosed speed, the vehicle lost motive power with the oil warning light illuminated. The contact was able to restart the vehicle; however, the failure recurred. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The manufacturer was not made aware of the failure. The contact related the failure to NHTSA Campaign Number: 22V746000 (Power Train); however, the VIN was not included in the recall. The failure mileage was approximately 41,000.
Seat belts, Aug 2, 2023
The contact owns a 2021 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, his son complained that the seat belt had tightened and locked and that he was unable to adjust the seat belt. Upon arriving at his destination, the contact stated that attempts to remove the seat belt had failed and the contact decided to cut the seat belt. The vehicle was not taken to the dealer or an independent mechanic. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 26,450.
Electrical system, Jul 25, 2023
So for the past year and half my cars left turn signal has been working intermittently. It just stops working and then it starts again. I have taken it to the dealer many times they changed out signal assembly i have taken many videos show proof. I am told at the dealer if you dont bring it in when it is not working then they cannot do anything even if i have video proof documenting this issue for the past year this is a serious safety issue that must be addressed. My next step is to contact Hyundai directly hopefully you can investigate this issue. This is very dangerous.
Power train, Jul 3, 2023
The contact owns a 2021 Hyundai Sonata. The contact received notification of the NHTSA Campaign Number: 22V746000 (Power Train) however, the contact stated that on numerous occasions while driving at various speeds, the accelerator pedal was depressed however, the vehicle decelerated and went into "fail-safe" mode. The vehicle was taken to the dealer where it was diagnosed that the transmission control unit software needed be updated. The vehicle was repaired; however, the failure recurred. Additionally, the contact stated that prior to the recall repair, while driving at an undisclosed speed, the vehicle failed to accelerate as needed. The vehicle was taken to the dealer and the transmission was replaced. The vehicle was not repaired. The manufacturer was notified of the failure and the contact was provided a case number and an appointment was scheduled to take the vehicle back to the dealer. The failure mileage was approximately 12,100.
Power train, Jun 19, 2023
Took vehicle in for transmission recall on June 12th. After picking up vehicle the vehicle it was shifting harshly. On the 17th my vehicle had a code come up that said to park it and contact the dealership ASAP. Transmission code P1C2D03. The recall was supposed to prevent this, not cause it.
Engine, Jun 13, 2023
The issue is well known across the DN8 platform, hundreds if not thousands of people have this problem.Car and driver even did an article on a car with this same 2.5L turbo DCT engine having the same problem! The problem is the ITMS or thermostat housing unit. I first experienced this getting on to a highway, I lost all acceleration, the turbo dropped to 0 pSI and I received an engine overheating warning on the dash. After pulling over the car resumed normal driving, but with oil temps running 30-40 degrees higher than normal. Since then, I have had loss of boost and acceleration when passing around cars which has almost caused accidents, oil temps constantly running very high and fans constantly running on full blast even after car is off. I have been to the service center 4 times, and they have failed to "replicate" the issue and stated the fan and oil problem is "normal" which it is not. This problem needs to be addressed before somebody gets seriously hurt due to loss of power unexpectedly while driving. PLEASE help! Thank you for your time.
Other or unspecified, Jun 13, 2023
The ITMS is failing causing engine over heating and loss of acceleration at higher speeds.
Structure, Jun 11, 2023
I was driving down the highway with my mom, no cracks in any of my windows before any of this by the way. And my sunroof exploded. Huge huge explosion sound. I thought something fell but there was nothing above us.
Engine, Fuel/propulsion system, Jun 8, 2023
When attempting to pass other vehicles or under quick acceleration such as an on ramp to the highway, the vehicle will experience a sudden loss of power and oil pressure resulting in a fail safe mode which limits your acceleration and causes a sudden decrease in speed and velocity. The issue results in the oil pressure light illuminating and requires the vehicle to be stopped and completely turned off to reset then once turned back on, the problem is “gone” until a sudden acceleration occurs again, which results in the same issue happening. There is a current recall out for similar models but my vin is not listed. I have approximately 50k miles on the car, and am the first owner.