NHTSA Complaint #11526848 — 2021 HYUNDAI SONATA

ENGINE issue reported to NHTSA

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Complaint Details

ODI Number 11526848
Vehicle 2021 HYUNDAI SONATA
Component ENGINE
Date of Incident
Date Filed
Mileage N/A miles
Crash No
Fire No
Injuries 0
Deaths 0
Vehicle Towed No
State VA

Consumer Description

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.

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