9 complaints reported

2021 Hyundai Sonata Engine

Owner-reported problems and safety issues filed with NHTSA. Review common failures, severity levels, and complaint trends over time.

Reports
9
Crashes
1
Fires
0
Injuries
0

Complaint Timeline

Chronological view of owner reports

Sep 2024 Crash

I purchased this vehicle brand new. It is still under factory warranty. It has approximately 14k miles on it. I have followed all recommended maintenance procedures. During a routine maintenance appointment at the dealership (Vancouver Hyundai 6802 NE 40th Street, Vancouver WA 98661) they identified a catastrophic engine failure due to internal component deterioration and the engine needs to be replaced. They have had my vehicle in their possession since [XXX] of this year for a total of 134 days. I have a case number at Hyundai # [XXX]. They have not been helpful in providing any information and as of now, I do not know when they even expect to receive a new engine. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Type: Vehicle, Vehicle: 2021 HYUNDAI SONATA, Manufacturer: Hyundai Motor America
Incident: Aug 2024
May 2024

The contact owns a 2021 Hyundai Sonata. The contact stated while driving 15 MPH, the contact noticed that the passenger’s side rear seat level had become elevated. The contact stated that his daughter who was seated in the child seat head had started touching the top of the sunroof. The contact became aware of a gasoline odor coming from the engine. The contact also became aware that the vehicle was consuming an abnormal amount of gasoline. There was no warning light illuminated. The vehicle was taken to the dealer however, the diagnostic test result was undisclosed. The dealer was unsure of how to service the vehicle. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was approximately 87,000. The VIN was not included.

Type: Vehicle, Vehicle: 2021 HYUNDAI SONATA, Manufacturer: Hyundai Motor America
Incident: May 2024
Mar 2024

faulty engine thermostat

Type: Vehicle, Vehicle: 2021 HYUNDAI SONATA, Manufacturer: Hyundai Motor America
Incident: Mar 2024
Nov 2023

My 2021 Sonata has 32,000 miles & it broke down in the middle of the road. My safety & my daughters safety were at risk. We could have been hit or killed. There were no warning lights. It had to be towed. Repair shop reports the transmission is no good. This vehicle should not have transmission issues. Hyundai will not even cover a rental car. The dealership can’t even work on it for 1-2 weeks. I work & have kids. I need a vehicle. The car breaking down in the middle of the road with no warning is dangerous.

Type: Vehicle, Vehicle: 2021 HYUNDAI SONATA, Manufacturer: Hyundai Motor America
Incident: Jul 2023
Oct 2023

I have a 2021 Hyundai Sonata SEL with a Smartstream 2.5L engine w/ GDI & MPI. I have have always heard a loud knocking noise coming from my engine since I got the vehicle when in park. When you are accelerating it hesitates and you can hear a knocking noise. I have taken it to the dealership multiple times and they were able to feel and hear what I was talking about but ensured me it was fine. Recently it has been a lot worse. On 10/18/2023 I was getting on to the highway from the feeder. I tried to accelerate to about 50 mph and I heard the same knocking noise and my rpms jumped all the way to the top. Then my car suddenly stopped getting on to the highway. It took it about a minute before I could start driving again. Luckily there was no one behind me because it could've been really bad. I got home and looked under the hood and it looked like oil had sprayed out of the engine. You could to see oil splatter on the fender. No one was hurt thankfully. I have been complaining about the knocking and hesitation while accelerating for almost 2yrs.

Type: Vehicle, Vehicle: 2021 HYUNDAI SONATA, Manufacturer: Hyundai Motor America
Incident: Oct 2023
Sep 2023

The contact owns a 2021 Hyundai Sonata. The contact stated while driving 45 MPH, the vehicle inadvertently lost motive power in the middle of the roadway and failed to restart. The vehicle was pushed to the shoulder of the roadway, where the failure persisted. No warning lights were illuminated. The vehicle was towed to the dealer, who determined that there was no oil in the engine, causing the engine to seize. The vehicle was then towed to another dealer, who confirmed the diagnostic results. The contact stated that an oil change was performed three days prior to the failure. The vehicle was not repaired. The manufacturer was notified of the failure, and a case was opened. The failure mileage was 44,000.

Type: Vehicle, Vehicle: 2021 HYUNDAI SONATA, Manufacturer: Hyundai Motor America
Incident: Sep 2023
Sep 2023

I was on the highway going 60 mph then all of a sudden my vehicles rpm's jumped way up to 8 and completely lost power was on I-45 in Conroe thankfully I was in the slow lane. I have attached pictures of my dash so I could get proof this time. I had to wait 7 minutes for the car to do anything. It also burned all of my engine oil. So had to buy oil for my vehicle. I just had my oil change 3 weeks ago. This has happened before on on the frontage road a few months ago. I have claims open with Hyundai Customer Care. I have been stating that my engine makes a clicking noise, it hesitates, and seizes all the time. I have had this problem since March of 2021 and I bought the car in January 2021. I know I am not a part of the engine recall but I should be. I am scared to drive it. Hyundai doesn't care one bit. Well enough is enough I will be getting rid of this death trap. If you are looking at Hyundai's don't waste your time or money.

Type: Vehicle, Vehicle: 2021 HYUNDAI SONATA, Manufacturer: Hyundai Motor America
Incident: Aug 2023
Jun 2023

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.

Type: Vehicle, Vehicle: 2021 HYUNDAI SONATA, Manufacturer: Hyundai Motor America
Incident: Jan 2022
Feb 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 failure and a case was opened. The failure mileage was 5,600.

Type: Vehicle, Vehicle: 2021 HYUNDAI SONATA, Manufacturer: Hyundai Motor America
Incident: Feb 2021

Trend Over Time

Complaints by year

Quick Summary

The 2021 Hyundai Sonata has 9 Engine complaints on file. 1 crashes have been reported. Review the timeline above for detailed owner experiences.