Complaint volume
115 consumer-submitted complaints are matched to this model year. Treat the count as a research signal, then read the actual summaries for repeated symptoms.
Complaint records
2021 Hyundai Sonata Complaints
115 consumer-submitted complaints on record for the 2021 Hyundai Sonata, grouped by component category.
115 Total complaints
7 Crash reports
0 Fire reports
2 Injury reports
Complaint data reflects consumer-submitted reports. A complaint is not proof
of a defect, recall, or manufacturer fault. Enriched severity fields come
from official bulk records when the complaint can be matched by ODI number.
Buyer interpretation
How to use these complaints before buying
Complaint records are most useful when they turn into inspection points, seller questions, and comparison checks against nearby model years.
Pattern to inspect
The most common categories are unknown or other, power train, engine. Use those categories as a test-drive checklist instead of judging the vehicle from the total count alone.
Severity flags
Enriched records include 7 crash reports, 0 fire reports, 2 injury reports, and 0 fatality reports. These fields come from complaint records and should be read in context.
Mileage clue
Mileage is available on 20 complaints, with an average reported failure mileage of 42,019 miles. Compare that with the mileage on the listing.
Questions to ask the seller
- Have you had any problems related to unknown or other, power train, engine?
- Can I see recent maintenance and repair records?
- Has the vehicle ever been towed, involved in a crash, or repaired for the same issue twice?
- Can we also check the recall record for this 2021 Hyundai Sonata?
Used-car checklist
Use these complaints before the test drive.
Build a buyer checklist to turn these issues into questions and inspection points.
2021 Hyundai Sonata
Build buyer checklist Compare with other years Sends year, make, and model to pre-fill your checklist.
How severe are the 2021 Hyundai Sonata complaints?
7 Crash
0 Fire
2 Injury
0 Fatality
5 Towed
1 Medical attention
What are the most common 2021 Hyundai Sonata complaint categories?
UNKNOWN OR OTHER 20
POWER TRAIN 12
ENGINE 10
ELECTRICAL SYSTEM 9
FUEL SYSTEM, GASOLINE 7
ENGINE,FUEL/PROPULSION SYSTEM 4
FUEL/PROPULSION SYSTEM 4
POWER TRAIN,ENGINE 4
VISIBILITY/WIPER 4
ELECTRICAL SYSTEM,ENGINE 3
115 total complaints on record
Latest complaints
| Date | Component | Summary | Severity | Mileage |
|---|---|---|---|---|
| Jul 2023 | POWER TRAIN | 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. | Crash: No Fire: No | 12,100 |
| Jun 2023 | POWER TRAIN | 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. | Crash: No Fire: No | Unknown |
| Jun 2023 | UNKNOWN OR OTHER | The ITMS is failing causing engine over heating and loss of acceleration at higher speeds. | Crash: No Fire: No | Unknown |
| Jun 2023 | ENGINE | 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. | Crash: No Fire: No | Unknown |
| Jun 2023 | STRUCTURE | 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. | Crash: No Fire: No | Unknown |
| Jun 2023 | ENGINE,FUEL/PROPULSION SYSTEM | 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. | Crash: No Fire: No | Unknown |
| May 2023 | SERVICE BRAKES,FORWARD COLLISION AVOIDANCE | Vehicle in front of me stopped. Six car lengths between us. I applied brakes, nothing, I even put my left foot on top of my right foot. There was plenty of time to stop but brake peddle wouldn’t go down, Felt like it was locked. Automatic Brake Sensor didn’t work either. Still waiting for inspection from manufacturer , 3 weeks. Never had any problems prior to this, After accident my warning came on about front collision failure . | Crash: Yes Fire: No | Unknown |
| Mar 2023 | VISIBILITY | The contact owned a 2021 Hyundai Sonata. The contact stated that while driving approximately 70 MPH, the sunroof suddenly fractured. The contact stated that there was no external cause to the failure. The vehicle was taken to the dealer. The vehicle was not diagnosed nor repaired. The contact decided to trade the vehicle. The manufacturer was not made aware of the failure. The approximate failure mileage was 13,300. | Crash: No Fire: No | 13,300 |
| Mar 2023 | STEERING,ELECTRICAL SYSTEM | After 9 months of ownership, on at least five (5) instances, the car has the following things happen at the same time: 1) all warning lights on the dashboard activate, 2) the battery discharge warning light activates, a loss of power steering, no speedometer, no cameras (rear or front), no AC, and all the safety functions are disabled including but not limited to: Forward Collision Warning, Parking Collision Warning, Automatic Emergency Braking, Lane Departure Warning, Rear Cross Traffic Warning. Yes, the car is available for inspection upon request. Safety is at risk by the loss of power steering and the deactivation of all safety functions. After each instance, the car has gone back to the manufacturer's dealer for inspection, they believed it might be an electrical issue after scanning for fault codes, but after 5 times, the dealer has not yet diagnosed the issue. | Crash: No Fire: No | Unknown |
| Mar 2023 | ENGINE | My 2021 Sonata has 32,000 miles & it broke down in the middle of the road. My safety & my daughters safety were at risk. We could have been hit or killed. There were no warning lights. It had to be towed. Repair shop reports the transmission is no good. This vehicle should not have transmission issues. Hyundai will not even cover a rental car. The dealership can’t even work on it for 1-2 weeks. I work & have kids. I need a vehicle. The car breaking down in the middle of the road with no warning is dangerous. | Crash: No Fire: No | Unknown |
| Feb 2023 | FUEL/PROPULSION SYSTEM,VISIBILITY/WIPER,FORWARD COLLISION AVOIDANCE | My car barely has 11,000 miles and just the other day it had about 20miles left of gas but as I was driving on the road it started to feel and seem like it was about to die on me, Also the front Wipers are not well restrained with the vehicle you can tell by the way it moves when Wipers are on....Also most of the Signals be It if something is in front of me and the signal goes off BUT THERES NOTHING THERE ...ALSO WHEN IM BACKING UP SOMETIMES the car itself will Force stop as if something is in the way ...BUT AGAIN NOTHING IS THERE AT ALL ...IT HAPPENS EVERY FEW DAYS ....I JUST PURCHASED THIS CAR ..AND REALLY THINKING IT WAS WORST MISTAKE W ALL THESE ISSUES ALREADY | Crash: No Fire: No | Unknown |
| Jan 2023 | ELECTRICAL SYSTEM | My vehicle is trending in theft, car was leased to me from Napelton in Lansing IL sept 2022. The first attempt of theft/break in UIC area Dec 10, second attempt in west Chicago area Jan 29. Both times I just cried and shut down. With having to contact the police awaiting the report process in middle of Chicago Winter left me cold and in terrible distress! This is a new vehicle for me which ultimately has caused me so much stress, anxiety, and frustration. I tried to trade it in but because of this nationwide issue that I was not aware of until the first incident! Still the theft numbers continue to rise! I am being told my cars value has depreciated from 25k to 15k which is not fair, and if I abandon this vehicle it will fall hard in my credit and ruin my chances moving forward with another vehicle!! With no where to turn and In dyer need of a reliable vehicle as I work and university student, having to constantly repair the windows after random theft attempts is a major safety hazard and for concerns of what can happen in a worst case scenario. I really need this issue to be addressed so that I can freely live my everyday life and not worry if I am leaving class or work that my car will not be there, or if my windows will be busted. I hope reaching out can help me get this vehicle traded in at a fair value! | Crash: No Fire: No | Unknown |
| Jan 2023 | STRUCTURE,VISIBILITY | As I was driving down the road I heard what sounded like a gunshot and glass shattering. Upon getting to my destination I found that my panoramic sunroof had shattered outward. | Crash: No Fire: No | Unknown |
| Dec 2022 | VISIBILITY/WIPER | *The front sunroof panel exploded toward while the car was running, but in the driveway in park. *Our safety was compromised by the shattered tempered glass falling into the car. *The problem was noted at the dealer, who stated they had not seen this happen before and believed it to be from a rock chip. *The roof has been inspected by the service department at the dealer, and pictures taken by them and by me. It has been reported to the manufacturer. *No problems noted prior to the “explosion”. Sitting in my car on a cold 27F morning, I started the car and turned on the front and rear defrosters and the heater. There was a light dusting of frost on the car. About a minute after I started the car, I heard a loud bang above me. When I opened the sunroof cover to see what the noise was, tempered glass shards fell in on me. When I got out of the car to see what had happened, the roof appeared to be exploded outward in circle about 10” across, although most of the sunroof glass was “crazed”. The car was not moving, had not had time to get warm, inside, there was no tree or other environmental hazard close to drop on the roof. | Crash: No Fire: No | Unknown |
| Dec 2022 | STEERING,FORWARD COLLISION AVOIDANCE | I leased a 2021 Sonata, and the Car has been a nightmare. My Car has been serviced by the dealership twice for a steering wheel that will not stop making noises. I am very concerned for my safety in this Car. The Wheel becomes hard to move. Also, last year, the Car was in the shop for four months while the forward collision sign needed to be fixed. The Car stopped twice. I am terrified to drive this car; it only has 9,200 miles. | Crash: No Fire: No | Unknown |
| Dec 2022 | POWER TRAIN | Car transmission seemed to make a "clunking" sound when selecting gear from park. The car would not accelerate, the throttle seemed to be stuck and the transmission would try to downshift, but the car was not picking up speed. I eventually pulled off the road into a parking lot and turned the car off. I then restarted the car and it seemed to clear the problem, but no warning lights ever came on, and no error codes were displayed on the instrument cluster. | Crash: No Fire: No | Unknown |
| Nov 2022 | ENGINE,FUEL/PROPULSION SYSTEM | Oct 12: Engine stalled exiting I95 in Kittery Maine. Engine light flashed but did not stay on. Was able to get to safe place but car would not go more than 15mph. Hampton Huyndai reported mis-fire but stated it cleared on its own. Oct 17th: Engine stalled on highway ramp to I495, nearly causing me to be rear ended by other vehicles. Car would not go more than 15 mph. Engine light stayed on. Towed car to Key Salem Hyundai, defective injectors, warrantee repair. Oct 23rd: Car stalls on I93, was able to take immediate exit and turn engine off. Engine light flashed but did not stay on. Took car in to Salem dealership on Oct 24th, no code found. Oct 25th: Car stalls again on city street. Light stays on, Salem dealership replaces cat. convrtr between Oct 26th through Nov 4th. Nov 9th: Car stalls again on city street. Light stays on, currently in Salem dealership. This is a safety issue, in two cases already this car has nearly gotten me in an accident on the highway. I am seeking arbitration for replacement. I am scared to drive this vehicle. I will have a third invoice pending this next repair. | Crash: No Fire: No | Unknown |
| Nov 2022 | POWER TRAIN,ENGINE | The contact owns a 2021 Hyundai Sonata. The contact stated while driving 65 MPH and attempting to accelerate, the vehicle failed to respond with the check engine warning light illuminated. The contact also heard a knocking sound coming from the vehicle. The contact pulled over on the side of the road and turn off and restarted the vehicle and the vehicle started operating as designed. The vehicle was taken to the dealer and the contact was informed that the transmission and engine needed to be replaced. The manufacturer was contacted but offered no assistance. A case was filed. The failure mileage was 2,700. | Crash: No Fire: No | 2,700 |
| Oct 2022 | POWER TRAIN | The contact owns a 2021 Hyundai Sonata. The contact became aware that the VIN was included in NHTSA Campaign Number: 22V746000 (Power Train); however, parts to do the recall repair were not yet available. The local dealer was contacted. The contact stated that the vehicle would delay while starting. The vehicle was taken to the dealer where it was diagnosed but no issues were found. The vehicle was not repaired. The contact stated that the manufacturer had exceeded a reasonable amount of time for the recall repair. The manufacturer was made aware of the issue and informed the contact that a recall notification would be mailed to him in December. The failure mileage was approximately 15,000. VIN tool confirms parts not available. | Crash: No Fire: No | 15,000 |
| Oct 2022 | POWER TRAIN | The contact owns a 2021 Hyundai Sonata. The contact stated that while driving at an undisclosed speed, the vehicle made abnormally loud sounds. The vehicle was taken to the dealer where it was diagnosed that the transmission needed to be replaced. The dealer informed the contact that they were awaiting approval from the manufacturer to perform the repair. The vehicle was not repaired and remained at the dealer. The manufacturer was made aware of the failure. Upon investigation, the contact related the failure to Manufacturer Recall Number: 236 (Power Train) included with the VIN; however, he had not yet received notification. The failure mileage was approximately 28,000. | Crash: No Fire: No | 28,000 |
| Oct 2022 | ELECTRICAL SYSTEM,ENGINE,FUEL/PROPULSION SYSTEM | UNKNOWN | Crash: No Fire: No | Unknown |
| Sep 2022 | VEHICLE SPEED CONTROL,ENGINE | Since we purchased this brand new vehicle, we have had in the dealership service department at a minimum of 5 times for same issue. The vehicle accelerates while stopped at a light so we have to put it in neutral to keep it from accelerating. Once we take out of Neutral and release the break, the vehicle accelerates rapidly without stepping on the gas pedal. The computer system always comes on warning that we need to take to dealership because there are engine problems. Then it goes off and comes on again. We have contacted Hyundai to file a complaint and it has gone no where. We have taken it to Hyundai dealership in Tucson and they keep replacing parts per Hyundai manufacturer service tech reps. per same Egr codes. We are taking the vehicle to the dealership again today 9/22/22 because it started again around 9/1/22 and we have been waiting for a loaner car again from Dealership for same problems. Meawhile, being forced to drive it due to only owning 1vehicle. Hyundai Manufacturer has continued to have dealership change out parts and this keeps happening. The vehicle has just over 25K miles on it to date. The first time we had it in the dealership for this problem was on 4/6/22. We have almost rearended several vehicles and are scared to death to drive this vehicle. It is a safety hazard. We purchased the 2021 Sonata vehicle brand new on 11/24/21 along with the lifetime parts and labor warranty. It had 15 miles on it. We also traded our 2018 Hyundai ELantra. We paid off the 2021 Sonata completely in 2021. The total cost of this transaction was $34,294.74.We have also followed all the Maintenance requirements. It is urgent that this complaint is investigated as soon as possible and Hyundai Manufacturer take responsibility now before someone gets killed. The vehicle is obviously a dangerous manufactured vehicle. | Crash: No Fire: No | Unknown |
| Sep 2022 | FUEL SYSTEM, GASOLINE | The contact owns a 2021 Hyundai Sonata. The contact stated while driving at various speeds, he smelled an abnormally strong fuel odor inside the vehicle. There were no warning lights illuminated. The vehicle was taken to the dealer who informed the contact that they could duplicate the failure. The vehicle was then taken to a second dealer, Wayne Hyundai Parts and Service (1244 NJ-23, Wayne, NJ 07470) who could not duplicate the failure. The failure persisted. The contact stated that after driving the vehicle, his entire body had a strong fuel odor. The manufacturer was notified of the failure and referred the contact to another dealer. The vehicle was not diagnosed or repaired. The failure mileage was approximately 21,000. | Crash: No Fire: No | 21,000 |
| Jul 2022 | POWER TRAIN | My transmission went bad on my new car. Didn’t have my car for 4 month August 12 2021 | Crash: No Fire: No | Unknown |
| Jul 2022 | AIR BAGS,FORWARD COLLISION AVOIDANCE,LANE DEPARTURE | Unknown | Crash: No Fire: No | Unknown |