2021 Hyundai Elantra Engine Problems

See attached document for complaint.

NHTSA ID

11746507

Incident

Mar 30, 2026

The contact owns a 2021 Hyundai Elantra. The contact stated that while driving approximately 70 MPH, there was an abnormal sound coming from the vehicle. No warning lights were illuminated. The vehicle was towed to a dealer to be diagnosed; however, the cause of the failure was not determined. The vehicle was not repaired. The vehicle was towed back to the dealer to be diagnosed; however, the cause of the failure was still not yet determined. The vehicle was not repaired. The vehicle was towed back to the dealer, where it was diagnosed with a coolant leak, and the thermostat needed to be replaced. The vehicle was repaired; however, the failure persisted. The manufacturer was notified of the failure. The failure mileage was unknown.

NHTSA ID

11731188

Incident

Nov 14, 2021

Subject: Vehicle Safety Complaint – Engine Failure – Hyundai To Whom It May Concern, I am submitting a vehicle safety complaint regarding a serious engine failure involving my Hyundai vehicle. The engine experienced a failure significant enough to require replacement. This raises serious safety concerns, as sudden engine failure can result in loss of power while driving, increasing the risk of an accident. In addition: •Hyundai Motor America has not adequately addressed the issue •My case (#xxxx) remains unresolved despite escalation •I have experienced delays, lack of transparency, and no meaningful resolution Given Hyundai’s known history of engine-related issues, I believe this may represent a broader safety concern affecting other drivers. I respectfully request that NHTSA: 1.Review this incident as a potential safety defect 2.Investigate whether this issue is part of a larger pattern 3.Take appropriate action to ensure consumer safety I am available to provide documentation and further details if needed. Sincerely, [XXX] [XXX] [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11730162

Incident

Mar 1, 2025

I owned a 2021 Hyundai Elantra N Line that experienced a recurring transmission issue. In warm weather conditions the transmission would intermittently slip and stutter, causing a jerky engagement when attempting to accelerate. In cold weather the vehicle operated normally without these symptoms. When the issue occurred, the vehicle would sometimes hesitate or fail to move forward smoothly when pressing the accelerator. This created unsafe driving situations, particularly when pulling into traffic or accelerating from a stop. On multiple occasions this behavior nearly resulted in rear-end collisions because the vehicle did not respond reliably to throttle input. The issue appeared to be temperature related, as the problem consistently occurred during warmer weather while the vehicle operated normally in colder conditions. Because the vehicle could fail to accelerate predictably, this created a safety hazard for myself and other drivers. I believe this may indicate a potential defect in the transmission system.

NHTSA ID

11722451

Incident

Jul 7, 2024

How are you? The problem with our Hyundai involves the engine and engine control system. My vehicle is equipped with the same 2.0-liter Nu GDI engine that Hyundai recalled in other 2021 and 2022 vehicles for engine stalling, internal engine damage, and fire risk. Although my VIN is not currently listed, the engine itself is identical to the recalled engines and is available for inspection. Since early ownership, the vehicle has repeatedly hesitated, surged, and jumped when accelerating from a stop, especially at stoplights and intersections. This unpredictable behavior creates a clear safety risk because the vehicle does not respond consistently in traffic and increases the risk of a collision. These issues are ongoing and reproducible under normal driving conditions. The symptoms have occurred many times and were not isolated events. The vehicle has been presented for service and the issues described. No misuse or maintenance-related cause has been identified. Prior to and during these events, the vehicle has shown reduced power, inconsistent throttle response, and hesitation. At times, warning lights and engine behavior consistent with internal engine distress have appeared. These symptoms match those described by Hyundai, Consumer Reports, and NHTSA in recalls involving this same engine. Hyundai has already acknowledged that this engine defect can lead to stalling, seizure, oil leaks, and fire, and that warning systems may not fully detect the problem until damage has already begun. Because my vehicle uses the same recalled engine and exhibits the same failure characteristics, I believe it should be reviewed as part of a recall expansion or defect investigation.

NHTSA ID

11712831

Incident

Jun 3, 2025

The contact owns a 2021 Hyundai Elantra. The contact stated that there was a knocking sound coming from the engine compartment while the vehicle was idling. The RPM fluctuated and the vehicle stalled while at a complete stop, and while shifted to park(P). The contact restarted the vehicle and was able to continue driving. The check engine warning light was illuminated. The failure had occurred intermittently. The vehicle was taken to the dealer, who confirmed that the 2.0L engine was known for similar issues. The dealer confirmed that the VIN was not included in NHTSA Campaign Number: 21V301000 (Engine). The vehicle was not diagnosed due to a lack of diagnostic trouble codes being displayed. The vehicle was not repaired. The manufacturer was informed of the failure, and a case was opened. The failure mileage was approximately 127,000.

NHTSA ID

11693336

Incident

Apr 14, 2025

Mileage

127,000 mi

Engine shots off while on the automatic stop and go idle . It is being doing it for a while but it is happening more often even with the auto idle off and it even happened at the freeway. It gives me a message to put it in park or neutral and turn the engine on manually. Making this a very dangerous situation because cars behind me don’t know that my engine suddenly shots off. Thanks

NHTSA ID

11678266

Incident

Aug 4, 2023

Heating core on car has gone out 3 times the first time costing $2,042.03 to repair, the two follow up ones were done under the warenty

NHTSA ID

11644100

Incident

Jan 23, 2025

Constant sound of flowing water throughout the front of the vehicle. Several service appointments later and there is still no solution to the issue that has been going on for over a year. Thia can be heard like a stream of water flowing. Engine ticking, loud rattling from engine. You can hear in from inside of the car.

NHTSA ID

11635269

Incident

Feb 1, 2024

I completed an oil change at Greggs oil express in Porterville California on 02-11-2023. I have the invoice. On 02-24-2023, I went out of town. At approximately, 5:00 pm, I heard a loud bang, large amount of oil pouring out of the bottom of the car, the car became disabled and I pulled over to the side of the road. I had it towed to the closest Hyundai dealership in Victorville Ca. They provided me with a report that stated when receiving my oil change stating due to the drain plug issue is a direct result of a third party and was not covered under warranty. I then made contact with my insurance, an investigator also reported the same. I have both reports. I have made contact with Greggs Express where I received the oil change and it was suggested to report the incident as they have come across situations like this with the particular vehicle. Therefore, I am now stuck. It is not covered under warranty, not covered under insurance, and the cost is 10,000. Besides the fact that I could have been injured.

NHTSA ID

11518666

Incident

Feb 24, 2023

The contact owns a 2021 Hyundai Elantra. The contact stated that while driving at an undisclosed speed, the vehicle overheated. The vehicle was taken to the dealer, who informed the contact there was a crack on the radiator. Additionally, the dealer determined that the failure was possibly collision related; however, the contact stated that the vehicle was not involved in a collision. The manufacturer was not made aware of the failure. The failure mileage was 39,573.

NHTSA ID

11512434

Incident

Mar 13, 2023

Mileage

39,573 mi

I picked up my Hyundai Elantra n-line today 12/1/22. My car was at the dealership for almost 3 weeks for transmission judder (shudder?) issues and they claim to have fixed the issue with a TSB (Technical Service Bulletin) from Hyundai with some snap and cable and additional work that was not disclosed. After picking it up and driving only 3 blocks my car went berserk where all dummy lights went on, the car's engine revved to redline, took off and suddenly the front wheels turned left (due to the avoidance features of the car perhaps) and I was able to pull the emergency break and stop the car. The car stopped luckily and if the e-brake did not work I would have ended up hitting the rear corner of a car and into a house. While the car was stopped, it was still on (unable to be turned off), all lights blinking including dummy lights and the car was showing still in DRIVE mode even though the revving stopped and the car was dead stop. After 10 minutes I was able to turn the car off (push button). Dealership dispatched a tow truck and now my car is back at the dealership for investigation. NOTE: TSB is something that is a known issue from Hyundai but not yet to the level of an official recall is what I was told by the dealership.

NHTSA ID

11495668

Incident

Dec 1, 2022

The contact owns a 2021 Hyundai Elantra. The contact stated while driving at 40 MPH, the vehicle shut off. The message "Put Car In Neutral And Restart Engine" was displayed. The contact stated that she shifted into neutral (N) and restarted the vehicle; however, the failure reoccurred persistently. The vehicle was towed to the dealer where it was diagnosed that an unknown activator needed to be replaced. The part was replaced. However, the contact stated that days after the repair, the vehicle would not exceed 25 MPH while driving. The contact pulled into a parking lot. The contact stated that a police officer was able to assist her with correcting the issue under the supervision of the dealer who was on the phone. The contact resumed driving and the vehicle responded as needed. The manufacturer was notified of the failure. The failure mileage was unknown. The contact later received recall notification of NHTSA Campaign Number: 22V354000 (Seat Belts), however, the parts to do the recall repair were not yet available. The local dealer was not contacted. The contact stated that the manufacturer had exceeded a reasonable amount of time to complete the recall repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. Parts distribution disconnect.

NHTSA ID

11488944

Incident

Oct 12, 2021

The contact owns a 2021 Hyundai Elantra. The contact stated that the vehicle was taken to the dealer for an unknown recall repair and for an oil change. However, while driving at an undisclosed speed after the services were performed, there was smoke coming from the exhaust pipe and the engine oil warning light was illuminated. The contact noticed that the engine oil had leaked onto the roadway while driving. Upon inspecting the vehicle, the contact noticed that the engine oil drain plug was missing. The dealer was made aware of the failure but provided no assistance. The vehicle was then taken to a second dealer, Columbia Hyundai (10981 Montgomery Rd, Cincinnati, OH 45249). However, the vehicle was not diagnosed or repaired and remained at the dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 15,500.

NHTSA ID

11478962

Incident

Aug 12, 2022

Mileage

15,500 mi

At about 11 months old my car suddenly seized while attempting to enter the highway. This came with no type of warning from the vehicle until the car had stopped and then every light on the cluster came on. I was fortunate not to be rear ended. The car was towed and 2 days later the dealership called to tell me there were no errors and NOTHING WAS WRONG with the car. I told them what had happened and they called later that day and I was informed that they needed to install and entire new engine assembly. The car only had 7000 miles on it and should not need a new engine. There is some major design flaw with this car which poses a safety issue. Additionally I looked at my service records for the car and it looks as if the dealership is trying to cover up the fact that a new engine was placed in the vehicle as it is listed as routine maintenance. Please look into this and contact me if needed

NHTSA ID

11473491

Incident

Dec 31, 2021

On 1/27/2022 my daughter was driving home from school in her 2021 Hyundai Elantra SEL which was purchased new on 6/19/ 2021 when at 5600 miles on the odometer a message came on the instrument cluster which read put car in neutral and turn off engine, when it was safe to do so she stopped the car and turned it off in the middle of a two way road because there was no shoulder and no place to exit the roadway when she tried to restart the car the engine would not crank or turn over to start the car so she called me and I called a tow truck while she was waiting vehicles behind her where forced to go around her car when it was safe for them to do so, the tow truck came and took her car to the dealership where she purchased it two days later they called and informed us the engine was completely seized up and that they would have to replace it with a NEW ENGINE despite the fact the original engine had oil and was only six months old with only 5600 miles on it.

NHTSA ID

11453121

Incident

Jan 27, 2022