Some Sonata (DN8, DN8A) vehicles may have DTCs P218100, P2181F0, and/or P2181F1 (Cooling System Performance) set in the Engine Control Module, resulting in an illuminated Check Engine warning lamp. Follow the procedure in this TSB to replace the Integrated Thermal Management (ITM) module and update both the Engine Control Module (ECM) and Transmission Control Module (TCM) if applicable. Follow the flowchart in this TSB to update the appropriate modules.
full bulletin at NHTSA ↗2020 Hyundai Sonata engine problems
moderate Owners of the 2020 Hyundai Sonata have filed 11 NHTSA complaints about the engine at roughly $3,100 to repair (U.S. federal records, as of July 2026). Source: NHTSA Office of Defects Investigation. See engine across all vehicles →
Complaints
11
Recalls
0
Avg fix
$3,100
| Model year | engine complaints |
|---|---|
| 2016 Sonata | 342 |
| 2017 Sonata | 292 |
| 2018 Sonata | 138 |
| 2019 Sonata | 68 |
| 2020 Sonata (this page) | 11 |
| 2021 Sonata | 19 |
| 2022 Sonata | 10 |
| 2023 Sonata | 13 |
Is there a fix? Manufacturer service bulletins
The manufacturer has issued service bulletins covering engine on this vehicle — documented repair instructions, service campaigns, or warranty extensions sent to dealers. A TSB isn't a recall (it's not a free safety remedy), but it's the manufacturer acknowledging the issue and how to fix it.
Certain Sonata (DN8) and Sonata (DN8A) vehicles may experience issues with the air conditioning due to damaged wiring in the engine room junction box. This bulletin provides instructions to replace the multi-fuse, reroute the damaged wiring using the blower wiring kit, and replace the fuse label.
full bulletin at NHTSA ↗Certain 20-22MY Sonata (DN8a), 21-23MY Santa Fe (TMa), and 22-23MY Tucson (NX4a) vehicles may experience a warning lamp illumination for a diagnostic trouble code P2181 that is related to the Integrated Thermal Management Module (ITM). Follow the service procedure outlined in this bulletin to replace the ITM.
full bulletin at NHTSA ↗This bulletin provides the procedure to update the Engine Control Module (ECM) and/or the Transmission Control Module (TCM) for 2020-2023MY Sonata (DN8/DN8a) vehicles to improve operation of the Idle Stop and Go (ISG) system. Under certain circumstances the vehicle may not restart after the ISG system has engaged and requires a manual restart due to the lack of intake manifold pressure recovery.
full bulletin at NHTSA ↗This bulletin provides important checkpoint guidelines when performing engine oil and filter change services.
full bulletin at NHTSA ↗Source: NHTSA manufacturer communications. Bring the bulletin number to your dealer or shop.
What owners are reporting 1 most recent
In May of 2023 my check engine light came on. Took the car to the dealer and the diagnosis was that the egr cooler was the culprit so they replaced it and everything was fine until 12/21/2023. I am driving on the highway and suddenly I hear a loud alarm and upon checking my instrument cluster I see a warning for engine overheating, the heat was on but suddenly the smell of something burning…
Had engine trouble with your 2020 Hyundai Sonata?
File a complaint with NHTSA → It's free, official, and how every report above got here — owner filings are the federal safety record this page is built on.
Common questions
How serious is the engine problem on the 2020 Hyundai Sonata?
It's a documented issue but not catastrophic. 11 complaints have been filed. Repairs average $3,100 and most owners catch it before it causes a breakdown.
At what mileage does the engine typically fail?
Based on the 11 complaints filed, engine issues most often appear around 27,530 miles. Some report problems earlier; some make it well past 150,000 with no symptoms. Maintenance habits matter — vehicles that received timely fluid services and were not regularly overworked tend to last longer.
What does it cost to fix?
Independent shops typically charge around $3,100 for engine repairs on this vehicle. Dealer pricing tends to run 20-40% higher. The exact figure depends on the specific failure mode, parts availability, and your local labor rates. If you're outside factory warranty, an extended service contract often covers this category.
Are there any recalls related to engine?
No active recalls currently cover engine issues on this vehicle. The complaints filed represent owner-reported failures that haven't risen to the level of a manufacturer-issued recall — but they're still worth knowing about before you buy or budget for repairs.
Related
Complaint and recall data sourced from the National Highway Traffic Safety Administration (NHTSA)
public records database. Verify the raw federal record at
nhtsa.gov/vehicle/2020/Hyundai/Sonata.
Severity ratings are derived from reported crashes, fires, injuries, and fatalities. Repair cost estimates are
independent-shop national averages and may differ in your area. Some links on this page are affiliate links.