Fuel system, gasoline
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.
NHTSA lists 4 safety recalls and 135 owner complaints for the 2021 Hyundai Sonata. Most complaints involve engine (34) and power train (25). The EPA rates it 27–32 mpg combined, and NHTSA gives it 5 stars overall.
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.
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.
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.
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.
Complaints for each Sonata model year we’ve synced.
| Model year | NHTSA complaints |
|---|---|
| 1996 | 24 |
| 1997 | 52 |
| 1998 | 50 |
| 1999 | 170 |
| 2000 | 278 |
| 2001 | 219 |
| 2002 | 326 |
| 2003 | 199 |
| 2004 | 202 |
| 2005 | 165 |
| 2006 | 1,047 |
| 2007 | 696 |
| 2008 | 425 |
| 2009 | 460 |
| 2010 | 345 |
| 2011 | 3,380 |
| 2012 | 1,559 |
| 2013 | 1,917 |
| 2014 | 751 |
| 2015 | 1,156 |
| 2016 | 728 |
| 2017 | 769 |
| 2018 | 375 |
| 2019 | 162 |
| 2020 | 183 |
| 2021 | 135 |
| 2022 | 96 |
| 2023 | 88 |
| 2024 | 48 |
| 2025 | 17 |
| 2026 | 3 |
“At approximately 130,000 miles, vehicle developed and internal coolant leak caused by a failed Exhaust Heat Recovery System (EHRS) in the center muffler assembly, matching TSB 23-EM-009H - a known manufacturing defect documented by Hyundai. Coolant has been slowly leaking internally into the exhaust system. The authorized Hyundai dealership initially failed to diagnose the internal leak and told me there was no leak and wanted to send me home. After pushing back, the internal leak was confirmed. If not caught, this defect could result in engine overheating or complete engine failure without warning. Hyundai Motor America has denied goodwill coverage despite this being a documented manufacturing defect.”
“My 2021 Hyundai Sonata N Line suffered a catastrophic, sudden total loss of drive power while operating at speed on a public roadway, creating an immediate crash hazard. The vehicle lost forward propulsion and the gear selector flashed a blinking 'R' when reverse was attempted. The vehicle was towed to an authorized dealer, [XXX] Hyundai Southtowne, where their factory GDS tool pulled transmission code P283601 (Shift Fork 'B' Position Circuit). This matches the exact critical safety failure path targeted by Federal Safety Recall 236 (NHTSA Campaign 22V-746) for the 8-speed wet-DCT high-pressure electric oil pump circuit failure. The vehicle previously received the 2022 software patch, but the underlying physical hardware has now actively degraded. The dealership is attempting to deny the federal safety recall remedy based on the vehicle's high mileage. An active corporate consumer affairs investigation has been opened under Case #XXX.”
“DESCRIPTION OF SAFETY DEFECT & IMMEDIATE HAZARD:My 2021 Hyundai Sonata SEL is currently exhibiting the most severe, catastrophic symptoms of the fuel tank expansion defect covered under NHTSA Campaign 25V796000. The fuel tank has expanded so drastically that it physically warped the structural interior of the cabin, violently popping the rear passenger seat completely out of its assembly while the vehicle was in motion. Furthermore, there is a constant, heavy, raw gasoline odor inside and around the vehicle. The vehicle is a documented, active fire, explosion, and vapor inhalation hazard. It is currently physically located at Sterling Hyundai in Lafayette, LA.DESCRIPTION OF MANUFACTURER NON-COMPLIANCE & REFUSAL TO REMEDY:Hyundai Motor America and Sterling Hyundai are in direct violation of their legal obligation to provide a safe, accessible remedy or interim safety accommodations under federal recall guidelines. An Executive Case Manager from Hyundai Corporate has officially refused to provide a direct-billed rental vehicle or a dealer loaner.Initially, a third-party rental vehicle was provided. However, that vehicle was compromised in an accident and wrecked…”
Towing, payload and dimensions aren’t in the EPA or NHTSA data, so we don’t list them.
| Version | City | Hwy | Comb. | Fuel / yr | CO₂ g/mi |
|---|---|---|---|---|---|
| Sonata Auto (S8), 4 cyl, 2.5 L, SIDI & PFI; Stop-Start · Front-Wheel Drive | 28 | 38 | 32 | $1,950 | 282 |
| Sonata Auto (S8), 4 cyl, 2.5 L, SIDI & PFI · Front-Wheel Drive | 27 | 37 | 31 | $2,000 | 293 |
| Sonata Auto (S8), 4 cyl, 1.6 L, Turbo, SIDI · Front-Wheel Drive | 27 | 37 | 30 | $2,100 | 293 |
| Sonata Auto (AM-S8), 4 cyl, 2.5 L, Turbo, SIDI & PFI · Front-Wheel Drive | 23 | 33 | 27 | $2,300 | 335 |
| Item | Miles | Time | Note |
|---|---|---|---|
| Engine oil & filter | 5,000–10,000 mi | 6–12 months | Follow the oil-life monitor if fitted |
| Tire rotation | 5,000–7,500 mi | Every oil change | Check pressure monthly |
| Engine air filter | 15,000–30,000 mi | 1–2 years | Sooner in dusty areas |
| Cabin air filter | 15,000–25,000 mi | 1–2 years | |
| Brake fluid | — | 2–3 years | Absorbs moisture over time |
| Coolant | 60,000–100,000 mi | 5–10 years | Long-life coolants last longer |
| Spark plugs | 60,000–100,000 mi | — | Iridium/platinum plugs at the long end |
| 12V battery | — | 3–5 years | Heat shortens battery life |
4 safety recalls as of Nov 10, 2026, according to NHTSA. Recall repairs are free at a dealer. Check your VIN to see whether your car is included and whether the repair was done.
Owners filed 135 complaints with NHTSA. The most-cited components are engine (34), power train (25), fuel/propulsion system (21). Complaints are unverified owner reports and aren't adjusted for how many cars were sold.
The EPA rates the 2021 Hyundai Sonata at 27–32 mpg combined, depending on engine and drivetrain (4 versions rated).
NHTSA's New Car Assessment Program gives the 2021 Hyundai Sonata 5 out of 5 stars overall.