2021 Hyundai Tucson: Engine complaints
Owner-reported issue (NHTSA complaints, not a recall)
Symptoms
NHTSA has 42 owner complaints for the 2021 Hyundai Tucson that list the engine component. Complaints are individual owner reports, not verified defects.
Examples:
- NHTSA complaint ODI #11766298 (filed 09/23/2026): “I took my car in to allen samuals hyundai dealership to have the 9c2 recall update completed on may 15th 2026. ever since then my vehicle has had a rough hesitation or sputtering when driving. on may 18th hyundai released a statement stating there was an issue with the update completed on the 9c2 ca…”
- NHTSA complaint ODI #11760640 (filed 08/29/2026): “Engine knock sensor went off and now the engine needs replacement due to faulty cylinder rod.…”
- NHTSA complaint ODI #11758305 (filed 08/20/2026): “See attached document for complaint.…”
Likely causes
These complaints do not establish a single root cause; read the examples above and get a diagnosis.
Fix, in plain English
No single fix is established by these reports. Check your VIN for open recalls at nhtsa.gov/recalls, ask a dealer about technical service bulletins (TSBs) or extended warranty coverage, then have the system diagnosed.
DIY difficulty: Pro
Internal engine work (lifters, oil consumption, fuel dilution diagnosis) requires engine teardown or dealer software/tests. (Our assessment.)
Cost
No sourced cost range for this issue. Get a written quote after diagnosis.
Typical parts (search links, no affiliate codes)
AutoZone · O'Reilly · Advance · RockAuto
Sources
Page last updated .