2020 Hyundai Elantra engine problems

ENGINE

The vehicle entered limp mode. The Hyundai dealer diagnosed a camshaft problem, said the repair would be covered, ordered the part, and began the work. After the engine was opened, the dealer noted sludge/varnish and denied coverage, claiming lack of maintenance. This VIN is included in safety recall 21V301 for improperly heat-treated piston oil rings on the 2.0L Nu MPI engine. Hyundai told NHTSA that chipped rings can scuff the cylinder bore, cause accelerated oil consumption, knocking, oil-pressure warning, connecting-rod bearing seizure, stall, and in limited cases fire. The published remedy is inspection of the cylinder bore and piston skirt, engine replacement if damage is found, and PNSS software, at no charge. Hyundai National Consumer Affairs Case #XXX. I sent a written demand that they complete Campaign 203 and not convert an open safety recall into a customer-pay job. On XXX, case manager Mohammad issued a letter denying only “limited warranty” coverage for lack of Owner’s Manual maintenance. That letter does not state whether the Campaign 203 bore/skirt inspection was done, does not state whether PNSS was installed, and does not decide the incomplete recall. Oil and filter were changed on a regular schedule by the owner’s family using the specified oil. A signed affidavit was provided. Hyundai’s warranty does not require dealer-only oil changes. The symptom of the recalled oil-consumption defect (varnish/sludge) is being used to refuse the recall remedy. The vehicle remains unrepaired. I have not authorized customer-pay work or disposal of parts. What I want NHTSA to do Record this as an incomplete recall remedy. Require Hyundai Motor America to complete Campaign 203 on VIN [XXX]: perform the official bore and piston-skirt inspection, replace the engine if abnormalities exist, install PNSS, and cover related camshaft/engine damage found when the engine was opened, at no charge. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11763344 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2020 Hyundai Elantra. The contact stated that while driving 25 MPH, there was an abnormal rattling sound coming from the engine, with the check engine warning light illuminated. The contact pulled over to the side of the road. The vehicle was restarted but unexpectedly stalled. The vehicle was taken to an independent mechanic and was diagnosed with camshaft failure. The vehicle was towed to the dealer and was diagnosed with engine failure caused by a misfire. The contact was informed that the engine needed to be repaired. The vehicle was not repaired. The vehicle was taken to another independent mechanic and was diagnosed with camshaft failure. The manufacturer was not made aware of the failure. The approximate failure mileage was 46,691.

NHTSA complaint #11761736 — an unverified report by a vehicle owner.

ENGINE

At 105,000 MI. My car stalled out and the engine stopped. It needs a new cam shaft, timing chain set, cam phaser and timing cover. We also had to replace the Variable valve timing solenoids as the metal melted.

NHTSA complaint #11755778 — an unverified report by a vehicle owner.

ENGINE

"I was not notified of Campaign 974 and later experienced engine problems/failure. I am requesting review of whether the campaign was completed and whether the failure is related to the condition the campaign was intended to detect. My engine failed while pulling up to a house, stopping, then preparing to move again the car stalled, car stalled, car would not start for several times tried, then started was able to drive for about 10 miles then stalled again and would not start, car has been intermittently working, car has recent and regular oil changes on time with correct oil and still failed now there is metal in the oil per the mechanics there is knocking sort of like ticking sounds - the car left me stranded due to the engine intermittently working and not working to start the car - the car will attempt to start then turn right off immediately after starting the car and sometimes not turn over the car also had been jumping when in stopped positions as soon as attempt to give gas ever so slightly

NHTSA complaint #11753202 — an unverified report by a vehicle owner.

ENGINE

Currently, there are 30,564 miles on my vehicle and I am the original owner of the vehicle since early 2021. This is a continuous intermittent problem that can occur at any time when trying to accelerate the vehicle. The vehicle could be moving down the road and you go to accelerate and the RPM's drop dramatically, giving you no power. The same thing has happened when trying to accelerate from a stop. The vehicle would start to accelerate and then all of a sudden the RPM's drop, giving you no power. I have had the vehicle to the dealership for this problem and I am being told that they can't do anything about it because they can't duplicate it. If this happened when it was necessary for me to get out of the way of a vehicle, an accident could occur, resulting in sirius injury or death. Also, there were no warning lights or check engine light that came on at any time when the problem presented itself.

NHTSA complaint #11742932 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2020 Hyundai Elantra. The contact stated that while driving, the vehicle unexpectedly stalled. The vehicle was able to restart. The check engine light illuminated. The vehicle was taken to an independent mechanic Camshaft sensor failure. The camshaft sensors were replaced; however, the issue persisted. The vehicle was then taken to the dealer where it was diagnosed with engine failure but the vehicle was not repaired. The manufacturer was notified of the issue. The contact associated the issue with NHTSA Campaign Number 21V301000 (Engine). The approximate failure mileage was 105,000.

NHTSA complaint #11740154 — an unverified report by a vehicle owner.

ENGINE

This complaint documents a recurring automatic transmission failure resulting in three complete vehicle shutdowns during active operation — two at highway speed and one in an active turning lane. The most recent failure occurred within 15 minutes of the vehicle being released from an authorized Hyundai dealership in College Park, Maryland, whose general manager admitted in a recorded call that the vehicle was released knowing the transmission was unrepaired and unsafe. The first failure occurred in 2025 on a highway with no prior warning. The vehicle was towed to the dealership, where the transmission was confirmed defective and repaired under warranty. The second failure occurred in January 2026, again on a highway with no warning. The dealership held the vehicle from January through May 2026 — four months — with no updates despite multiple owner inquiries. In April 2026 the dealership confirmed the transmission had failed again and was seeking Hyundai corporate authorization for the warranty repair. On May 21, 2026 I was told the vehicle was ready and the transmission had been fully repaired under warranty. This was false. On [XXX], within 15 minutes of leaving the dealership, the transmission failed a third time, completely shutting the vehicle down in an active turning lane with no warning. The general manager at Hyundai College Park later admitted in a recorded call that the transmission was never repaired and the vehicle was released only to recover the dealership's rental car, with full knowledge it was unsafe. All three failures were confirmed by the authorized dealer. Component is available for inspection. NHTSA investigation and recall consideration requested. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11739852 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2020 Hyundai Elantra. The contact stated that while driving at an unknown speed and at a stop, the vehicle lunged forward. The RPM increased and decreased without applying the accelerator pedal. The check engine light was illuminated. A mobile mechanic reset the codes but was unable to determine the failure. The vehicle was taken to an independent mechanic who referred him to the local dealer. The local dealer was contacted, who stated there was a transmission pressure sensor issue. which prevents the service from being performed under Hyundai Service Campaign 863 T5B Bulletin: 20-01-028H. The manufacturer was contacted, but no additional assistance was provided. The failure mileage was approximately 76,000.

NHTSA complaint #11738079 — an unverified report by a vehicle owner.

ENGINE

My engine failed due to a known piston problem code P1327. The recall 203 was performed 7/1/22 which put in a sensor so the dealership said that Hyundai said they do not have to fix it because it is out of warranty at 141,000 miles and was manufactured in South Korea so they say it doesn't qualify for the extended warranty Recall 203 Dealer Best Practice Date: October 12, 2021 Subject: HMA Recall 203 – Nu 2.0L Atkinson Engine Inspection and Replacement - (TSB #21-01-054H-1) - Remedy Available v3 Updates To This Document Date • TSB# 21-01-054H-1 – The TSB supersedes TSB # 21-01-054H to revise the Parts and Warranty Information sections, specifically related to add engine and service kit part numbers and op codes for engine replacement. 10/12/21. My car is available for inspection. The sensor light came on on the highway when the engine was already out of oil which caused the failure. The car could have caught fire or stalled on the highway which is the safety issue. The vehicle was inspected by Tires Plus and got the P1327 code and also the Wallace Hyundai dealer in Ft. Pierce, FL which got same code.

NHTSA complaint #11733944 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2020 Hyundai Elantra. The contact stated that the vehicle unexpectedly turned off while driving 25 MPH on a local road. The engine symbol was displayed. Additionally, the battery was drained. The vehicle was taken to an independent mechanic, and the battery was replaced three times. Additionally, the computer was replaced, and the contact was informed that the powertrain system had failed. The local dealer was contacted and confirmed that there was no extended warranty on the vehicle. The vehicle was not diagnosed or repaired. The contact called the financial institution and the dealer who sold the vehicle about the warranty. The manufacturer was not notified of the failure. The failure mileage was approximately 70,000.

NHTSA complaint #11733271 — an unverified report by a vehicle owner.

ENGINE

The check engine light came on at 101000 miles. I took it to the shop and the mechanic said there was no oil on the dipstick and he put in oil and said we need a new engine because it is knocking. We have noticed the vehicle has a rough idle now.

NHTSA complaint #11731605 — an unverified report by a vehicle owner.

ENGINE

Said it needed a map sensor. I replaced it and it started acting g crazy. Dying at stop lights making weird noises. I finally threw cod P0011 so I bought the oil control valve before it arrived ny car died. It skipped 5 or 6 teeth. 3,900 left to pay on it. Im a single mom and need my car to provide [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11729460 — an unverified report by a vehicle owner.

ENGINE

Within a matter of a few days my car has been stopping by itself. The car was smoking and stopping in the middle of the highway, my dealership is proving me with a new engine but is trying to have me come out of pocket for an fuel injector, please help !

NHTSA complaint #11729565 — an unverified report by a vehicle owner.

ENGINE AND ENGINE COOLING

The contact owns a 2020 Hyundai Elantra. The contact stated that while driving at an undisclosed speed, there was a low rattling sound coming from the engine compartment. Upon checking the oil, the contact found the oil level was low and added approximately two quarts of oil. The contact stated that 2-quarts of oil were added monthly because the oil level and consistently low. However, there were no signs of an oil leak while the vehicle was parked. The vehicle was not diagnosed or repaired; however, during a routine oil change, the contact was informed that an oil gasket might need to be installed. The vehicle was not repaired. The manufacturer was notified of the failure. The failure mileage was unknown.

NHTSA complaint #11727946 — an unverified report by a vehicle owner.

ENGINE

I see there was a P0420 error code related to catalytic converter oil consumption recall, but when I put in my VIN it said no recalls. This is for a 2020 Hyundai Elantra 2020. The problem comes and goes and was able to be reproduced or confirmed by a dealer Hyundai. The warning lamps, messages comes on frequently and was reportedly fixed charges $2000 for a sensor. I the code and it is all over the internet that it is a recall.but does not show up with VIN.i need assistance with getting this fixed at the dealer

NHTSA complaint #11727146 — an unverified report by a vehicle owner.

ENGINE

burning/ oil/gas in oil/stalling/engine light on...open recall of other models of same car not includin tghis one.seems to be same issue.

NHTSA complaint #11724072 — an unverified report by a vehicle owner.

ENGINE

The contact owns a 2020 Hyundai Elantra. The contact received notification of NHTSA Campaign Number: 21V301000 (ENGINE). While driving at an undisclosed speed, the check engine warning light illuminated, and the vehicle was pulled over to the side of the road. The vehicle was towed to the residence. The contact then towed the vehicle to the dealer, where it was diagnosed with piston oil rings failure, and it was determined that the engine needed to be replaced. The dealer informed the contact that the manufacturer had refused to honor the recall repair. The vehicle remained at the dealer unrepaired. The manufacturer was not notified of the failure. The failure mileage was unknown.

NHTSA complaint #11719235 — an unverified report by a vehicle owner.

ENGINE

My car just lost all power and stopped on the side of the road after making a weird noise under the hood

NHTSA complaint #11718016 — an unverified report by a vehicle owner.

ENGINE

This vehicle’s engine failed on 10/25/21. This was 2 months after it was purchased. When we tried to have a Hyundai dealership diagnose the car, they said it would be an extended amount of time before the could look at it. When they finally did, they said it was not eligible for the warranty or recall relief. I reached out to the Hyundai corporate office and received no assistance. They tried to say it was due to no drain plug. It was recommended that we take it to another dealership who said the same thing. We ended up paying out of pocket to replace the engine. The mechanic who replaced the engine said there was no oil splatter under the car that would indicate an oil leak. Now on 1/15/26, the 2nd engine has now failed for apparently the same recall. For either engine there was never any warning of low oil or any evidence under the car of a leak.

NHTSA complaint #11712293 — an unverified report by a vehicle owner.

ENGINE

Engine is stalling and consuming oil at a higher then normal rate. Knock sensor is having issues at 24k miles both part of recall campaign 974 and recall 203. Took the auto to dealer for service and was told Hyundai would not honor the recall due to a branded title which now puts me in a scenario of possibly engine stall in the middle of highway traffic.

NHTSA complaint #11709281 — an unverified report by a vehicle owner.

ENGINE

Reporting motor has a cold start ticking sound coming from the motor.

NHTSA complaint #11707760 — an unverified report by a vehicle owner.

ENGINE

Subject: Abnormal Engine Failure – Hyundai Case #[XXX] I am filing this complaint regarding my Hyundai vehicle, which suffered catastrophic engine failure at approximately 150,000 miles. While the vehicle is outside the standard warranty, this type of failure is not consistent with normal use or expected durability. Hyundai Motor America has acknowledged receipt of my certified demand letter (Case #[XXX]) but has refused to provide coverage, instead directing me to pay for towing and diagnostic costs. This position is unacceptable given Hyundai’s history of abnormal engine defects and related settlements. Key points: • The failure is abnormal and consistent with systemic defects Hyundai has faced in prior litigation, including the Theta II and Lambda II engine defect class actions, which resulted in recalls and settlements covering millions of vehicles. • Hyundai has previously extended goodwill repairs and recall coverage for similar failures, even outside warranty periods. • Engine failure at this mileage presents a serious safety hazard, including risk of stalling, fire, or loss of power while driving. • Hyundai’s refusal to cover towing and diagnostic costs places an unfair burden on consumers and may violate consumer protection statutes. Requested Action: I request that the agency investigate Hyundai’s handling of abnormal engine failures, ensure compliance with consumer protection and safety laws, and require Hyundai to provide coverage or reimbursement for towing, diagnostic, and repair costs in cases where engine failure is abnormal and unsafe. Supporting Documentation: • Certified demand letter sent to Hyundai Motor America. • Hyundai’s written denial (Case #[XXX], dated December 11, 2025). • Vehicle mileage and details of engine failure. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA complaint #11704643 — an unverified report by a vehicle owner.

ENGINE

my engine started to make a horrible noise and the car won’t start anymore. Hyundai engines are known to burn oil and don’t light the low oil dash light until it is too late. Other Elantra trims have a recall for Hyundai to fix this yet mine does not.

NHTSA complaint #11704321 — an unverified report by a vehicle owner.

ENGINE

Cruise control on 55mph, car has slowed down going straight no uphill or downhill and accelerator did not work nothing blocking the accelerator. Had to pull over to a shoulder to shut engine off and on to drive. Tapping cruise control up to speed up in regulated area such as from 55 to a 65mph zone.. cruise control speed lowered. Attempting to speed up with accelerator still only slowing down. 3 times this year I had to change spark plugs within a 6 month period Error code p0302. Replaced battery alongside. Continues p0302 code. Replaced all coils and spark plugs still p0302. Climbing uphill vehicle sometimes looses power that happened twice in 2025 and twice in 2022. 3 times in 2024. That i must turn on hazards and floor the accelerator to gain speed on up hills in neighborhoods going 25 mph. I have dropped to 10 mph. I get oil change regularly. Always when due. Every few months I make sure to get a full car inspection to make sure everything is in proper working order.

NHTSA complaint #11701387 — an unverified report by a vehicle owner.

ENGINE

At around the 120K mile odometer reading check engine light came on and upon checking the oil, noticed it was 1/2 qt. down in spite of a recent oil change. There were no other issues apparent to our mechanic. At the next oil change, we asked the techs to be sure to tighten the oil pan and all components as we mentioned the drop in oil after the previous oil change. This time, only 10 days after the oil change (we have been using hybrid blend since purchasing the vehicle new), the check engine light went on again and the oil was down a quart with no signs of leaking. Our mechanic checked it again and told us of many Hyundai oil consumption issues and suggested we check for a recall. My vehicle was not included in the oil consumption recall despite having the same year, model and engine as many of the other "certain" vehicles. We are currently negotiating a solution with Hyundai Motor Corp.

NHTSA complaint #11701279 — an unverified report by a vehicle owner.

ENGINE

The vehicle is burning the engine oil. I get regular oil changes on time. I was told by the service center I had low oil at an oil change. It was changed and then again it a few months later I burned through the oil again. I checked it and there was very little oil. There is no leak. It is just burning it.

NHTSA complaint #11692251 — an unverified report by a vehicle owner.

ENGINE

2020 Elantra built in Alabama with 2.0L engine has P0016 code and severe oil sludge at 73K miles - identical to Recall 21V301 symptoms but excluded because manufactured in Alabama not Korea. This appears to be the same defect affecting a different production batch.

NHTSA complaint #11690688 — an unverified report by a vehicle owner.

ENGINE

The contact's mother owns a 2020 Hyundai Elantra. The contact was informed that the vehicle occasionally stalled without warning and would be immediately restarted to continue driving. Additionally, the vehicle would hesitate before slowly accelerating. The contact stated that there was a knocking sound coming from the vehicle at start-up, with a constant ticking sound coming from the engine compartment. The check engine warning light was illuminated. There were signs of an oil leak, and the oil needed to be changed more frequently. While changing the oil, the owner noticed smoke coming from inside the oil pan. The traction control warning light and the ABS warning lights were illuminated. The vehicle was taken to the dealer, who diagnosed that the ABS module and piston rings in the engine had failed. The vehicle was not repaired. The contact became aware of NHTSA Campaign Number: 21V301000 (Engine); however, the VIN was not included. The manufacturer was informed of the failure and confirmed that the vehicle was not covered under recall or warranty. The contact was referred to the dealer for assistance. The failure mileage was 101,000.

NHTSA complaint #11688132 — an unverified report by a vehicle owner.