2023 Hyundai Sonata Engine Problems

I own a 2023 Hyundai Sonata SEL. Over approximately three years, the vehicle experienced four separate incidents involving sudden loss of engine power and recurring fuel injector/powertrain problems. Three of these incidents occurred while the vehicle was being driven on interstate highways, creating serious safety concerns. The first incident occurred on XXX, on [XXX] [XXX]. My daughter was driving the vehicle at the time when it suddenly lost power while traveling on the interstate. She had to maneuver the vehicle to the shoulder under unsafe traffic conditions. The second incident occurred on XXX, on [XXX] near [XXX]. I was driving the vehicle when it again experienced sudden loss of power while traveling at highway speed. The third incident occurred on XXX, in [XXX]. The vehicle experienced another significant power-loss event and required roadside assistance. The fourth incident occurred on XXX, on [XXX]. The vehicle again experienced a sudden loss of engine power while I was driving on the highway. Despite multiple repair attempts, including repairs related to the fuel injectors, the same or substantially similar power-loss problem continued to recur. Because the vehicle has repeatedly lost engine power while being driven, including multiple incidents at interstate highway speeds, I believe this recurring condition presents a serious safety risk. I am reporting these incidents so NHTSA can evaluate whether this may represent a broader safety-related defect affecting this vehicle model. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11755422

Incident

Jun 30, 2026

This is an extremely common issue plaguing Hyundai & Kia vehicles with the Theta III 2.5L Turbo engine, Such as Kia K5 GT, Hyundai Sante Fe, Hyundai Santa Cruz, & Hyundai Sonata N-Line. Its a failing ITM (integrated thermal management) unit or otherwise known as an ITMS unit. There is a rod within the ITM that prevents proper control of the flow of cooling the oil and engine coolant of the engine. Results in Cooling issues, such as a cold lower radiator hose while the engine is hot, or 'limp mode' during acceleration, that causes a sudden loss of power while trying to merge on the expressway. There has been other Kia models and years that have had TSB's related to fixing this issue, but Hyundai has released nothing. I have uploaded an example of one of the TSB's that do not apply to my car. Technical symptoms often include: Fans running 100% full duty (high) while the lower radiator hose stays cool. Or Fuel dilution or a 'rich' running engine. Because the engine is overcooling that keeps the car's fueling rich and in a open loop mode affecting emissions and contaminating oil. Personal Details of exactly what happened when i noticed mine was failing. I ran home on my lunch break, and while accelerating on a ramp to get up on a highway, my car started beeping and flashing "Engine Overheated" and i immediately let off the gas with preparation to pull over. The second i left off the gas, the coolant temp within 1-2 seconds went from a little over 3/4 the way up the gauge back to normal a little below half temp. I resumed driving a 3 mile drive back to work, with it showing normal temps the rest of the way. I popped the hood when i got to work to see if coolant was low, and it was completely normal, a little over halfway between the min/max lines. The car continues to run hot, often with the cooling fans running at 100%.

NHTSA ID

11737860

Incident

Feb 25, 2026

The contact owns a 2023 Hyundai Sonata. The contact stated that while his wife was driving at an undisclosed speed, the message "Engine Overheated" displayed. The contact checked the Hyundai app, but it showed no failure. The contact's wife drove to their son's residence, who inspected and discovered that there was no coolant in the engine. The contact's son added coolant to the engine. The vehicle was taken to the dealer, who replaced the coolant valve, exhaust muffler assembly center, clamp assembly exhaust pipe, two gasket exhaust pipes, and added coolant. The contact related the failure to Technical Service Bulletin: 23-EM-009H (EHRS Coolant Leak Repair); however, the vehicle was not covered under the TSB. The manufacturer was made aware of the failure, and a case was filed. The failure mileage was approximately 18,500.

NHTSA ID

11737251

Incident

Apr 17, 2026

Mileage

18,500 mi

See attached document for complaint.

NHTSA ID

11728741

Incident

Feb 25, 2026

Battery Management System completely exhausting the 12V battery resulting in the car acting as if it has no power. When this happens, you can't unlock the door or open the trunk. On two separate occasions, I have encountered a complete loss of power in my Sonata Hybrid, preventing me from unlocking the trunk or doors upon returning from extended trips. The first incident occurred after a ten-day absence last Fall, and the most recent was on Saturday, March 14, 2025. During the latest incident, I returned from a seven-day trip and found my vehicle parked at Orlando International Airport. Upon approaching the car, I anticipated being able to unlock the trunk, load my luggage, enter the vehicle, and drive home. However, once again, the vehicle was unresponsive. Accessing the car required removing the cap from the door handle and manually inserting the key, a process that took approximately ten minutes, which was particularly inconvenient and concerning in an airport parking lot. This situation was even more challenging considering I am a [XXX] woman of smaller stature attempting to resolve this issue alone at night. I believe this poses a serious safety concern for all owners under similar circumstances. Following the incident last Fall, I brought my Sonata Hybrid to Key Hyundai in Jacksonville. I was informed that this is a known issue for which there is a recall; however, my vehicle model year is not included in the affected range. It was suggested that I would need to manage this problem independently. I believe this recurring issue represents a known vulnerability that could potentially expose Hyundai and its dealerships to liability should an owner suffer harm while addressing this malfunction. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11724724

Incident

Mar 14, 2025

Recall 286 my vehicle suffered from this causing heat module failure misfire in cylinder 2 and high pressure in gas tank. Sports Hyundai had previously done a 180 day repair under recall 9b1 for an expanded gas tank after the repair the car suffered from the updated recall 286 . I brang to the dealership 4 times with check engine and misfires and limp mode between 57k and 68k they refused to fix the car under recall 286 and cleared all the codes and continued to make me leave in a unsafe car. On February 14th it sport Hyundais negligence was the direct cause of an auto accident were the car was unable to move out the way because of lack of power /limp mode. I begged them in the final days of me having the car to fix it and saying I didn’t feel safe and they wouldn’t without an extensive amount of money I could not provide . I’m currently filing a claim with Hyundai consumer affairs and the dca in Newark and also my senators office and I have a lawyer also who might help I wish to report this to the NHTSA.

NHTSA ID

11722063

Incident

Feb 14, 2026

Vehicle WITHOUT WARNING will start to jerk then go into “limp” mode. Pressing on gas pedal makes the revving noise but with not physical movement made. This has happened on MULTIPLE occasions (13 times in 4 months) including in the snow and on the interstate while driving at 70mph where no shoulder is available to pull over. Car was taken to dealership 3 different times with no actual diagnosis, tests were ran all 3 times with nothing. Eventually the 3rd time at the dealership I was told the transmission was being replaced although they were not sure what actually caused the issue (this is written in the service report by the rep/mechanic). CAR REMAINS UNSAFE AND UNRELIABLE. Livelihood of myself, family and other drivers is at risk EVERYTIME I put the car in drive due to this mechanical issue. NO WARNINGS NO POWER NO FIX.

NHTSA ID

11721841

Incident

Dec 22, 2025

My Hyundai Sonata 2023 is experiencing two recall codes. The first one was 9b1 which was resolved, but the other one is indefinite which is 286. I dropped my car off on December 4 of 2025 and a month later Hyundai’s corporate team reached out to discuss the state of my car. They asked me for things such as the payoff balance of what I owe through CarMax who I’m financing the car from, they asked me the mileage on the car, the registration and the lien. They then told me they would provide me with an update by certain dates it’s been over two months and I haven’t received any updates. The car shop called me to come pick up my car because one of the issues was resolved, but after reviewing the recall code 286 and seeing that there is very much so a safety risk when driving the car, I ultimately chose to leave the car with Hyundai. Hyundai has been unsuccessful with providing me with the solution. I’ve waited two months almost 3 months and I believe that this vehicle is a lemon and I need a solution. Hyundai took back the loaner, I have nothing now and they keep telling me they’re going to follow up, but have not followed up with anything I need help. I don’t want to risk my life, driving the car and being paranoid that it could catch on fire and harm me or other people driving in it please help.

NHTSA ID

11718375

Incident

Dec 4, 2025

My car was having an issue where it was losing all the coolant, causing my engine to overheat twice while driving down the highway. Unfortunately I couldn't find a leak anywhere and there was no fluid leaking in my garage. I lost an entire reservoir of coolant overnight. After taking my car to the dealership to get repaired, I was told that it was leaking my coolant into the exhaust system and burning it up. I was also told "it was a know issue, they had a bulletin from Hyundai on how to fix the problem, and Hyundai completely redesigned the part to stop the leak and it had to be special ordered." I was without my car for a week and left with a $1300 bill as apparently it was not covered by my warranty. I have no idea how a known issue is happening so frequently that requires a nationwide bulletin and a part redesign, yet somehow is recalled. Especially considering it left me stranded on the side on the side of the highway in Indiana during a snow storm but someone seriously needs to investigate it.

NHTSA ID

11704347

Incident

Dec 2, 2025

I am reporting a serious coolant system defect on my 2023 Hyundai Sonata Hybrid with about 13,500 miles. The vehicle develops an internal coolant leak while driving. Coolant burns off and white steam/smoke comes out of the exhaust, especially during acceleration. When this happens, the coolant level drops quickly, the interior heater stops working, and the car soon displays an engine overheating warning, forcing me to stop driving. This has happened multiple times and makes the vehicle unsafe. When I checked under the hood, coolant was at a low/empty level after overheating events. The car becomes undriveable once the alarm appears. I took the vehicle to a Hyundai dealer, and even though the vehicle is only 2 years old, they told me it was “out of warranty.” I had to pay about $1,500 for repairs, and since the dealer refused a loaner, I paid $250 for a rental car. I called Hyundai USA on 9/13/2025 and opened Case Number XXX. Hyundai acknowledged they are aware of coolant issues on the Sonata Hybrid but said no recall exists. This issue appears widespread. Many other owners report the same symptoms: white exhaust steam, coolant smell, coolant loss, no interior heat, and engine overheating. Hyundai released TSB 23-EM-009H, describing a failure where coolant leaks internally in the Exhaust Heat Recovery System (EHRS), causing white smoke and overheating—matching my symptoms exactly. This defect is a safety hazard because overheating can occur suddenly while driving, risking engine damage or breakdown in traffic. I request NHTSA investigate this issue as a potential recall-level defect on the 2023 Sonata Hybrid. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11700476

Incident

Sep 13, 2025

Car stalls and shuts down while shifting to park or reverse and when slowing to turn or stopping. Also the media screen will black out and not work at times.

NHTSA ID

11700089

Incident

Nov 17, 2025

The fuel injectors failed on my Hyundai Sonata in two instances. Once on 5/23/24 and once on 9/7/25. During the first instance, I was driving on a local road when the accelerator stopped working and the engine started sputtering. We were fortunately able to stop at a nearby parking lot before the engine completely stopped working. During the second instance, I was also driving through a local road when the accelerator stopped and the engine started sputtering again. This time, we weren't able to reach a safe stopping point and the engine died on the road. My family was with me at the time, so we had to push the car in neutral to the closest safe space. In both cases, our safety and the safety was others was put at risk as the car become unable to accelerate, and the car stops moving. We had to get out on the road and push the car with oncoming traffic. The problem was confirmed by the dealer in both cases, and they replaced the fuel injectors in both cases. So far, they've replaced 3 out of the 4 fuel injectors so I still drive in fear of another fuel injector causing a breakdown while I'm driving. There were no warnings or symptoms prior to the failure so there was no way to know to stop driving and to stop in a safe spot. We were fortunate to be able to move the car to a safe place for both instances, but if this had happened on the highway or secluded location, our lives could've been at risk. I've requested Hyundai to replace the last fuel injector but they're refusing to do so. I only feel safe driving in local roads or short highway trips as I fear for the reliability of my car, my safety, and the safety of others.

NHTSA ID

11695686

Incident

Sep 7, 2025

I was driving my 2023 Hyundai Sonata with 22,000 miles on I-96 near Grand Rapids Michigan at or slightly below the speed limit of 70 MPH. Suddenly, with no advance warning of any kind, the engine shut down. I was able to coast and maneuver to the right shoulder of the road while avoiding traffic, including a large tractor trailer that almost hit us. The vehicle than had just enough power to get off the next exit and on a local side street. At that point the vehicle would not restart and you could smell a strong odor of fuel. I called Hyundai and they sent a tow truck to take it to the nearest dealer. (I am 700 miles from home). The dealer's service department diagnosed the problem then replaced the fuel injectors still under warranty.

NHTSA ID

11684700

Incident

Aug 12, 2025

Coming home from work I stopped at a red light and when I tried to accelerate the vehicle was surging and jerking shaking and wouldn't pick up speed 2 min later the check engine light appeared flashing thankfully I was 5 min from home got the car towed the next morning to hyundai dealership said it was an cylinder misfire the car only has 30,000 miles on it

NHTSA ID

11672179

Incident

Jul 3, 2025

On June 4 as son was turning, the car started shaking & went to park. He managed to slip into a nearby parking spot & tried to reverse. The car turned on, put into reverse & then after about 2 seconds it went to park & stopped. This happened several times. It was towed to the dealer who today, June 10, reported it was a transmission flaw. The car was being driven at about 30 mph on a 2 way street. Had it been on the interstate at a higher speed, it may have caused a dangerous situation with a sudden stop.

NHTSA ID

11666202

Incident

Jun 4, 2025

2023 Sonata N-Line, complete loss of power while driving on seven (7) occasions over the past year. In all cases above 60mph creating a dangerous condition to myself and fellow drivers while attempting to pull to the side of the road while rapidly losing speed. In all seven (7) cases, the DTC code is P065312. I have asked the dealership to note the recurring issue in my service records and I have reached out to Hyundai, mostly so that if I am involved in a serious accident because of this issue, there is a paper trail for legal purposes. The dealership folks are nice but basically unless the car rolls into the dealership with smoke pouring out of the engine, they want to charge a diagnostics fee and keep the car for multiple days which isn't helpful because like most, I need the car and the issue is extremely sporadic. It is disappointing and I hope Hyundai takes note and provides remedy for the issue sooner rather than later as this is my sixth (6th) Hyundai vehicle and really do like the car otherwise. All incidents below: 01/23/2025 - 9531 miles 01/20/205 - 9128 miles 12/15/2024 - 5500 miles 12/13/2024 - 5374 miles 11/22/2024 - 2409 miles 01/12/2024 - 568 miles 01/08/2024 - 554 miles

NHTSA ID

11638560

Incident

Jan 23, 2025

For like the fifth time while I'm driving the car just dies. I can be going 55 I can be going 70 and the dashboard lights up like a Christmas tree and the car just dies. I have to pull the car over to the side and I have to turn it off and restart it again. And then about 3 days later the check engine light will go away. This seems like a software issue but Hyundai and my local dealer cannot help me I'm going to get killed in this thing. I can't take it on the highway I can barely take it down the street because it could go out on me while I'm driving and I could be in the middle lane and I could get killed. They tell me they can't replicate the issue but it's a software issue somebody needs to do something before I get killed. Every single light on the dashboard turns on and the engine just dies. This is like the fifth time this has happened. I think this car is a lemon but no one will help me.

NHTSA ID

11622068

Incident

Oct 26, 2024

I was driving on the interstate at interstate speeds and the car started to lose power. I was able to steer the car to a safe location and call roadside assistance. It appears that the engine control system had a failure in one of the control modules. The problem was reproduced at the time that I dropped the car off with the service center. The history of the issues for the vehicle are available. My safety was put at risk because the car lost power at high speed and I was only able to limp to a safe location. No warning lights happened until the issue was already taking place. After being notified by my Hyundai app, I was able to discover that the vehicle had a history of having this code (I have only owned the car for 32 days)

NHTSA ID

11603350

Incident

Jul 19, 2024

On two separate occasions, one at @9500 miles and the next at @19,000 miles the car engine started shaking and lost all power while driving. Unable to steer car. Both times towed to dealer and they say it needs new spark plugs and need to clean cylinders. They do not know root cause of problem and have not done any testing of the engine, no leak/compression testing. Dealer refuses to cover cost of repairs saying out of warranty but cannot give any assurances this won’t happen again. I’ve requested they contact Hyundai engineers to find out what’s causing this and, to date, they’ve done nothing. Vehicle is unsafe to drive and is still at dealership with no reason to underlying issue.

NHTSA ID

11594317

Incident

May 24, 2024

The car would not accelerate, nor switch gear while I'm driving middle of the highway. The car engine started to shake after my car wouldn't switch gear. The car engine would not start after turning the car off and caused a engine misfire. The transmission gear has a hard time switching gear from 0-40mph. This same incident occurred twice since purchasing the car in late November 2022.

NHTSA ID

11586734

Incident

Apr 18, 2024

I have had three occasions where the dashboard lights would flash and the car would lose all power. The first occasion occurred on December 29th at around 12:20 pm at a crowded intersection. The dashboard lights lit up and all of a sudden the car had no power at all. I managed to get it through the intersection and pull it off to the side of the road. To start it up I have to TURN OFF THE CAR by putting it in park and start it up again. This is stressful and terrifying to think about if this had happened on the freeway. Additionally, I took the car to get serviced and was charged a $1,800 bill to fix it in January. This repair took two weeks to complete. The car has since turned off two additional times on February 15th going down a hill at 40 mph and March 26th on a mountain road going 60 mph. I am very concerned this will happen on the highway and I will get into a serious accident or worse. To make matters more difficult, I have taken the car back to the Hyundai dealer again to have it looked at in April and will most likely be without the car for at least another week. I bought the car brand new and the check engine light has gone off four times since then.

NHTSA ID

11581001

Incident

Dec 29, 2023

2023 Hyundai Sonata N-Line bought on [XXX]. Engine Control System failed 2 times w/in first 4 months. 1ST ENGINE INCIDENT ● [XXX] (Approximately 1:30 p.m.) ○ I was driving (1,949 miles on odometer) at an intersection when car lost power, lights on dashboard starting flashing & ignition shut off in the middle of intersection. ○ On dashboard notification stated “A possible condition with your engine control system has been detected with your 2023 Hyundai Sonata [XXX] ) on [XXX] at 1:25 p.m. A full system check is recommended to be done soon”. I also received notification via email. ○ Couldn't get appointment until [XXX] Cesar advised me they did diagnostic test & test drive & couldn’t find the problem. They made no repairs & made a notification in system of this problem. He stated that if it happens again to bring the car back. 2ND ENGINE INCIDENT ● [XXX] ○ My husband & I were driving (4,177 on odometer) & I was pulling out of a side street to make a left hand turn into a busy 4 lane street & as I drove ½ way across street my car lost all power, lights on my dashboard started flashing, ignition shut off & two cars were driving towards us about to T-bone us my driver's side. Cars braked suddenly to avoid hitting us. ○ On the dashboard of my car was a notification stating “A possible condition with your engine control system has been detected with your 2023 Hyundai Sonata [XXX] ) on [XXX] at 1:15 p.m. A full system check is recommended to be done soon”. I also received this notification via email. Dropped car off at Fontana Hyundai on [XXX]. Did diagnostic test & engine specialists inspection; couldn't find problem They said we will replace this part and hope it doesn't happen again. How do you put someone back in a car when you haven't diagnosed the problem; that's a serious safety issue, my life is endangered. Supposed to pick car up [XXX]. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11576458

Incident

Nov 26, 2023

Driving going 30 mph, vehicle stopped accelerating. Error code was Engine Control System failure. Codes P2178, P0301 and P0087F0 were shown at dealership. Car was taken to dealership for repairs where the fuel injector on cylinder #1. 16 days after receiving car back, we went to start the car and it wouldn't start. After several attempts, gasoline began spewing from the car leaking an entire tank of gas on our garage floor and driveway. Very dangerous! Being towed to dealership again today.

NHTSA ID

11568524

Incident

Dec 30, 2023

The contact owns a 2023 Hyundai Sonata. The contact stated that on two separate occasions while driving at various speeds, the vehicle started to shake, and the vehicle lost motive power. The vehicle was pulled over to the side of the roadway and turned off. The vehicle failed to restart on both occasions. The vehicle was towed to a dealer where it was diagnosed that the fuel injector needed to be replaced. The vehicle was repaired. The manufacturer was notified of the failure. The failure mileage was approximately 11,000.

NHTSA ID

11554363

Incident

Aug 24, 2023

Mileage

11,000 mi

Vehicle’s front collision sensor popped up on dash, vehicle lost all power. Almost was hit by a group a semi trucks hauling a wide load that wouldn’t have been able to stop in time. This is the 3rd time it has happened in a week and a half.

NHTSA ID

11554293

Incident

Nov 9, 2023