2021 Hyundai SONATA problems and owner complaints
Explore the records behind recurring owner reports.
Key facts
130 owner complaints analyzed
4 distinct recall campaigns
38,000 mi median reported failure mileage
Scope: 2021 model year. Data snapshot: . 24 complaints include usable failure mileage.
Most common problems
Engine is the most frequently named component, appearing in 34 of 130 complaints (26.2%). A complaint can name multiple components.
| Topic | Matching reports | Share of complaints |
|---|---|---|
| Transmission and shifting | 18 | 13.8% |
| Braking behavior | 14 | 10.8% |
| Fuel system concerns | 14 | 10.8% |
| Engine operation | 10 | 7.7% |
| Electrical and battery issues | 10 | 7.7% |
| Steering behavior | 2 | 1.5% |
Topic matches use published keyword rules. They describe mentions, including negations or comparisons, and do not confirm a diagnosis. Read the matching rules.
Component breakdown
Number of unique complaints naming each component. Top eight shown.
| Category | Count |
|---|---|
| Engine | 34 |
| Unknown Or Other | 32 |
| Power Train | 22 |
| Fuel/Propulsion System | 20 |
| Electrical System | 16 |
| Fuel System, Gasoline | 10 |
| Visibility/Wiper | 8 |
| Air Bags | 4 |
Engine: 34; Unknown Or Other: 32; Power Train: 22; Fuel/Propulsion System: 20; Electrical System: 16; Fuel System, Gasoline: 10; Visibility/Wiper: 8; Air Bags: 4
Reported problems by failure mileage
Complaint counts in mileage bands. These are not failure rates per vehicle or mile.
| Category | Count |
|---|---|
| Under 25,000 | 9 |
| 25,000 to 49,999 | 7 |
| 50,000 to 74,999 | 3 |
| 75,000 to 99,999 | 3 |
| 100,000 to 149,999 | 2 |
| 150,000 and above | 0 |
Under 25,000: 9; 25,000 to 49,999: 7; 50,000 to 74,999: 3; 75,000 to 99,999: 3; 100,000 to 149,999: 2; 150,000 and above: 0
Under 25,000 miles has the most reports with usable mileage (9). 106 complaints have missing, zero or invalid mileage.
Complaints over time
Year the complaint was filed, not the vehicle model year or incident year. The snapshot year is partial.
| Category | Count |
|---|---|
| 2021 | 9 |
| 2022 | 18 |
| 2023 | 22 |
| 2024 | 15 |
| 2025 | 29 |
| 2026 | 37 |
2021: 9; 2022: 18; 2023: 22; 2024: 15; 2025: 29; 2026: 37
Pattern summary
Engine leads the component reports. Transmission and shifting appears in 18 complaint narratives. Braking behavior appears in 14 complaint narratives. Fuel system concerns appears in 14 complaint narratives. Use these patterns to inspect individual reports and prepare questions for a mechanic.
Calculated from recorded counts. An AI narrative has not been published for this selection.
Complaint evidence
Examples provide context, not a representative sample or a verified diagnosis.
Owner report 11438217 · 2021-10-26 (October 26, 2021)
On August 23rd, 2021, I was on a business trip between High Point, NC and Greenville, SC. I was operating my own vehicle as the mode of transport. Upon arrival in Greenville, the car began behaving strangely. The transmission was not shifting at typical intervals, at times racing the engine at low speeds. After restarting the vehicle, there was a brief return to normal. Then the vehicle reported a "Check Engine" light and the transmission stopped functioning entirely. Due to capacity issues, I was unable to utilize a local dealership. …
Owner-reported narrative. Look up ODI 11438217 at NHTSA ↗
Owner report 11442458 · 2021-12-02 (December 2, 2021)
The contact owns a 2021 Hyundai Sonata. The contact stated that while the vehicle was at an independent mechanic for an oil change, the mechanic diagnosed the vehicle with transmission fluid leaking from the engine. The mechanic informed the contact that the transmission fluid leakage was flammable. The dealer was made aware of the failure but informed the contact that they were backed up with other vehicles and could not diagnose the vehicle for approximately three weeks. The vehicle was not repaired. The manufacturer was made aware of the fai…
Owner-reported narrative. 5,600 miles reported. Look up ODI 11442458 at NHTSA ↗
Owner report 11511856 · 2023-03-14 (March 14, 2023)
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 …
Owner-reported narrative. Look up ODI 11511856 at NHTSA ↗
Owner report 11520558 · 2023-05-05 (May 5, 2023)
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 .
Owner-reported narrative. Look up ODI 11520558 at NHTSA ↗
Owner report 11603481 · 2024-07-19 (July 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 dumpi…
Owner-reported narrative. Look up ODI 11603481 at NHTSA ↗
Owner report 11645969 · 2025-03-03 (March 3, 2025)
The contact owns a 2021 Hyundai Sonata. The contact stated while pulling out of a parking lot, the vehicle failed to accelerate as intended and started shaking abnormally. The check engine warning light was illuminated. The vehicle was taken to the residence. The vehicle was towed to an independent mechanic where it was diagnosed that the fuel injector needed to be replaced. The vehicle was towed to a dealer where it was diagnosed that all four fuel injectors needed to be replaced. The vehicle was repaired. The manufacturer was not notified of …
Owner-reported narrative. 47,000 miles reported. Look up ODI 11645969 at NHTSA ↗
Owner report 11492999 · 2022-11-10 (November 10, 2022)
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 of…
Owner-reported narrative. Look up ODI 11492999 at NHTSA ↗
Owner report 11456267 · 2022-03-11 (March 11, 2022)
I turned on a highway and had gotten my car up to 45 mph when a deer came out of nowhere and I slammed into it hard back on January 12th. The car only suffered cosmetic damage thankfully, but the air bags did not deploy. I have since then found out that the front air bag crash sensors are in a spot where they are practically useless unless you hit something pretty high up and destroy the headlights in the process. In my opinion, this is a serious safety issue, and when I contacted Hyundai about it, all they told me was to go to the dealershi…
Owner-reported narrative. Look up ODI 11456267 at NHTSA ↗
Owner report 11496631 · 2022-12-08 (December 8, 2022)
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.
Owner-reported narrative. Look up ODI 11496631 at NHTSA ↗