2018 Hyundai Sonata Complaints

ENGINE — Filed 07/10/2025

Vehicle caught fire after repeatedly taking it to Hyundai for service . I complained about the oil consumption and knocking noises while the vehicle was still under warranty and it was denied.

POWER TRAIN,ELECTRICAL SYSTEM,ENGINE — Filed 03/16/2023

The vehicle had safety and mechanical problems shortly after purchase, even with low mileage. The issues included warning lights, abnormal noises, repeated mechanical failures, and poor performance that affected the safe operation of the vehicle. These problems started early and continued over time despite repairs and maintenance. Before the incident, the vehicle showed signs of malfunction, including instability while driving and loss of normal performance. These symptoms created an unsafe driving condition and increased the risk of a crash. I believe the vehicle had defects from the beginning that affected safety. The failure contributed to the accident that occurred while driving on the highway, putting my life and my family at risk.

POWER TRAIN,ELECTRICAL SYSTEM,ENGINE — Filed 01/29/2026

Unknown what system failed. The vehicle is at an impound lot and can be inspected on request. Police and fire department were on the scene. Police did provide a report # , and fire department provided a fire rescue case number. Safety of driver was put at risk due to the fire and potential for burning or even death. Other drivers could have been at risk if traffic had not allowed for quick movement to side of the road. No warning lamps had been on prior to the drive and none prior to fire. First indication was a burning smell while driving. As pulling over, another driver honked to alert to fire he could see from rear of ca,. before I noticed the flames. Upon getting out of car first flames I saw appeared to be coming from under passenger side of car. The fire department arrived about 15 minutes after pulling to side of the road. The car was fully engulfed in flames. They then extinguished the fire. Police saw vehicle and insurance will examine. Apparently this is a known issue in Hyundai of which this vehicle had no open recalls pertaining to such.

AIR BAGS — Filed 12/16/2025

I am Detective [XXX] #XXX with Austin Police Department Vehicular Homicide Unit and I worked a fatal crash [XXX]. The damage to the vehicle two vehicle should not have caused a death. The airbag became detached from the steering wheel and impaled into the drivers chest. I do have pictures but they are crime scene pictures and pictures of the decedent so I am not attaching them but if someone contacts me I can arrange that. I do not know the speed but I am going to image the module next week. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

ELECTRICAL SYSTEM — Filed 05/28/2025

The contact owned a 2018 Hyundai Sonata. The contact stated that upon her daughter reaching her destination, she observed brown smoke emanating from the engine compartment. Within a short while, the vehicle became completely engulfed in flames, prompting a bystander to attempt to extinguish the fire with a fire extinguisher, but was unsuccessful. Local emergency services arrived and were able to extinguish the flames. A fire report was filed, and it was indicated that the fire may have been electrical, but an exact cause had not been determined. A police report was filed, and no injuries were reported. The vehicle was towed to a tow yard and deemed a total loss by the contact's insurance provider. The manufacturer was not notified of the failure. The failure mileage was 125,000.

ENGINE — Filed 06/28/2025

My 2018 Hyundai Sonata caught fire unexpectedly while parked. The engine suddenly began smoking, then the vehicle ignited and was severely damaged. I am still financing the vehicle through Capital One. After researching, I discovered that my vehicle’s engine is part of a known Hyundai recall due to fire risk (Theta II engine defect). I had no prior warning or engine-related issues that would have predicted this. I strongly believe the fire was caused by a manufacturing defect, and I’m requesting that NHTSA investigate Hyundai’s handling of this issue and ensure victims like myself are compensated — even if not physically injured. I can provide photos, a fire report, and additional documentation if needed. Please let me know the next steps or if I qualify for any related recall recovery programs.

ENGINE — Filed 05/03/2023

Engine began making knocking sound then car while in the highway was not able to accelerate. This slowdown put driver at risk for highway accident. Took car to dealership. They said the engine needed replaced then the next day said no Hyundai said it needed a sensor. This was a bandaid fix as it continued to go through oil faster than it could be changed this led to engine shake and knocking several months after the band aid fix. The car was not able to accelerate again. Again took it to Hyundai dealership said it need an oil test required us to do and pay for an oil change when we had just done one. Drive the 1000 miles brought it back failed the oil test said they need to do some sort of engine clean. Hyundai refused as the car doesn’t have oil change records for the first three years. No record of oil change was recorded even though they were completed. It being five and six years ago we don’t have receipts but believe these were part of the lease and completed at the dealership at no cost. Now Hyundai not even doing the rest of the oil test but say engine needs replaced however they will not cover the repair. We have all records after the car was purchased off the lease other car we own has full oil change records but since we are not able to locate and no one recorded they have denied the repair of a known issue with their engine. This engine issue needs a full investigation as they are trying to get away with not fixing THEIR known problem. This is a driving hazard for the cars still on the road as the engine will suddenly lose the ability to accelerate and could cause a major accident.

SERVICE BRAKES — Filed 06/18/2024

The contact owned a 2018 Hyundai Sonata. The contact stated that while driving at 35 MPH, a pedestrian alerted him that the vehicle was on fire.  The contact noticed that the rear portion and driver side of the vehicle was on fire.  While traveling around a curve the brakes became inoperable the contact jumped out of the vehicle. he contact sustained injuries to his left shoulder and leg and medical attention was provided.  There were no warning lights illuminated. The vehicle continued to roll as it was burning.  The vehicle crashed into a dirt mound at the end of a hill. The fire department was on the scene to extinguish the fire. There were four gallons of fuel on the ground. The vehicle was towed to tow lot. There was no police report fire or air bag deployment. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The insurance company deemed the vehicle a total lost. The failure mileage was approximately 105, 000.

SEAT BELTS,ENGINE — Filed 09/15/2023

I was the owner of a 2018 Sonata until I was t-boned and the car was totaled. I started to make a left turn into a school parking lot when the engine kind of stalled or more like stuttered and did not go forward as usual. The oncoming car then struck me before I was completely in the driveway. My vehicle was totaled as was the other one. Fortunately no one was on the passenger's side where the other car hit me. However the seat belt did not engage which resulted in me slamming very hard into the steering column. This resulted in bruised on my right side which cleared up in several weeks, but, unfortunately, I received a heart contusion on my left side which is still causing shortness of breath. Hyundai will not acknowledge a problem with the engine or the seat belt.

ELECTRICAL SYSTEM,ENGINE,FUEL/PROPULSION SYSTEM — Filed 02/06/2024

The car was sitting in the parking lot and randomly black smoke started coming from it and then it turned into fire within in minutes. No one was in the vehicle and 911 was contacted.

ELECTRICAL SYSTEM,SERVICE BRAKES,FORWARD COLLISION AVOIDANCE — Filed 02/09/2024

Vehicle 1 operating normally in traffic on [XXX] in Westfield MA. Operator 1 notices alert on dashboard. As Operator 1 looks down briefly and returns eyes immediately to the road, she sees Vehicle 2 braking to slow or stop. Operator 1 depresses brakes, but vehicle does not slow as it usually does, nor does Automatic Emergency Braking engage as it always has in the past. Front of Vehicle 1 makes contact with rear of Vehicle 2. Dashcam footage appears like brakes did not activate at all, either manually or automatically. Vehicle 1 airbags deploy. Westfield Police respond, as well as Westfield Fire, who cut the battery cable. Vehicle towed to Interstate Towing, Inc. Yard 5, 20 Clifton St, Westfield, Ma 01085. (413) 593-1900 interstatetowing.com. Owner 1 viewed vehicle at tow yard, and noted that the battery was completely melted, with only portions of the plastic casing along with internal plates visible. Much of the plastic and rubber components immediately adjacent to battery location were melted and deformed. As a layperson, it almost appears as though the battery was in the process of shorting out just prior to the collision, possibly rendering many of the safety systems inoperable. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

POWER TRAIN,ELECTRICAL SYSTEM — Filed 08/16/2023

The contact owns a 2018 Hyundai Sonata. The contact stated that while driving approximately 60 MPH the vehicle suddenly began sputtering and then completely stalled. The contact had to coast to the side of the road and noticed the check engine light illuminated. After approximately 10 minutes, the vehicle was able to restart. When starting the vehicle there would be a sputtering followed by the vehicle shutting off. The failure began to occur while idle as well. The contact stated that while attempting to reverse out of a parking spot the vehicle suddenly accelerated forward instead. As a result, the vehicle ended up crashing into a concrete light post. The air bags did not deploy. There were no injuries or medical attention needed. The vehicle was able to be driven after. No police report was filed. The vehicle had been towed to the dealer who had stated that the starter relay issue may be the cause, however, because of not being able to duplicate the failure they were unable to give an official diagnosis. The vehicle had not been repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 86,000.

UNKNOWN OR OTHER — Filed 08/05/2023

UNKNOWN. I noticed that there was a check engine light on and I took it to autozone to have it checked out, they told me that it was coming back with the code of an o2 sensor. I thought nothing of it until it started not wanting to start right. On July 1, 2023 I took my car in to the dealership for an oil change and they never said anything about why my car was doing a delayed start. It would eventually start but it took at least a minute. I bought a new battery from walmart to put in my car so that it would not do the delayed start, but it kept doing it anyway. Finally decided to take it to a mechanic and the first time that he started it took at least a minute, he realized that he didn't have his computer (code reader) with him so he turned it off. When he returned with the code reader he plugged it in and started the car then it started smoking, smoking turned into fire that caused the entire underside of my hood to melt including engine, electrical harness, belts, battery and much more. If it wasn't for the mechanic's quick thinking by putting out the fire while calling 9-1-1, the fire would have gone to the fuel tank and exploded. Yes, the safety of others was put at risk.

ENGINE — Filed 06/16/2023

I first reported issues with my vehicle to a local Hyundai dealer January 16, 2023. I was advised I couldn’t get an appointment until March 8, 2023. Since March 8, 2023 I have taken my car to the dealer my numerous times for a series of testing over the course of 3 months. I was advised my car was burning too much oil of oil per 1000 miles. I was also advised that the transvalve and engine needed to be inspected by an adjuster to determine a faulty engine in order to get approval from the manufacturer. My car was at the dealer for almost a week. On June 15, 2023 the Hyundai dealership advised the engine was faulty. I was also advised warranty approved for a new engine due to faulty engine/oil consumption. I was advised to pick up my vehicle from the dealership. On June 16, 2023 I picked up my vehicle. I was told by the dealership to keep driving my vehicle until the new engine came in due. I was denied a loaner/rental at the time even though they knew the car had a faulty engine. Immediately after leaving the dealership dealership my car started smoking. I pulled over immediately got out. The car caught on fire and burst into flames. This was a very dangerous safety risk. It caused panic attacks, anxiety, headaches, and lots of sleepless nights. If I hadn’t gotten out sooner I could’ve been severely injured or dead. The car is with the insurance company. A field investigation has been done by the insurance. They determined faulty engine and total loss if the vehicle. It is still available for inspection if needed. There were no warning lamps or messages before the car started smoking or caught fire.

SERVICE BRAKES, HYDRAULIC — Filed 02/24/2023

The contact owns a 2018 Hyundai Sonata. The contact stated that while driving at various speeds, the brake pedal would depress to the floorboard with the maintenance message displayed on the instrument panel. The vehicle was taken to a dealer; however, the dealer was unable to determine the cause of the failure. One day while driving the vehicle, there was an abnormal tapping sound coming from the brake pedal while being depressed. The failure persisted while the brake pedal was depressed and the vehicle drove through a concrete post and a fence, causing damages to the post and the fence. The contact stated that the air bags deployed upon impact. Medical attention was not sought at the scene. The contact sustained bruising all over her body. A Police report was filed. The vehicle was driven back to her residence by a neighbor. The dealer and the manufacturer were notified of the failure. The vehicle was not repaired. The failure mileage was approximately 30,000.

AIR BAGS — Filed 12/02/2022

Hello im jesus ochoa on December 2 of 2022 i had a car accident i went underneath a simi truck and my air bags didnt deployed on my 2018 hyundia sonata and im worry of the new car i have from hyundai if the air bag didnt deployed on my 2018 hyundia

ENGINE — Filed 03/26/2022

The contact's son owned a 2018 Hyundai Sonata. The contact stated while her son was driving at 68 MPH with a passenger in the front passenger seat, he noticed a burning odor and he noticed smoke coming inside the cabin through the AC vents. There was no further information provided. The contact's son pulled into a gas station and saw fire underneath the hood. The contact's son and the passenger immediately exited the vehicle. The contact's son was able to extinguish the fire with the assistance of bystanders who used fire extinguishers. The vehicle was towed to the dealer. The vehicle was not diagnosed or repaired. The vehicle was then repossessed by the auto financing bank. The manufacturer was notified of the failure and informed the contact that they could not assist as the failure was caused by a missing oil cap. The failure mileage was unknown.

FIRERELATED — Filed 09/29/2022

The contact owned a 2018 Hyundai Sonata. The contact stated that while driving, the vehicle caught fire without warning. No warning lights illuminated. The air bags did not deploy. The fire department was notified and was able to extinguish the fire. The origin of the fire was unknown. The contact sustained a burn to her inner left ankle. Medical attention was required. A police report was filed. The vehicle was towed to a tow yard. The dealer was notified of the failure, but no assistance was provided. The vehicle was not diagnosed or repaired. The vehicle was deemed totaled by the insurance. The manufacturer was not notified of the failure. The failure mileage was approximately 112,000.

VEHICLE SPEED CONTROL — Filed 03/13/2022

The contact owns a 2018 Hyundai Sonata. The contact stated that while her daughter was reversing out of a parking space, the vehicle experienced unintended acceleration. The vehicle drove forward and crashed into a brick post. The contact's daughter did not sustain any injury but later received medical attention. There were no airbags deployed. A police report was filed. The vehicle was towed to a tow yard where the dealer later picked up the vehicle and took it to their location. The contact was unaware of what was repaired since the dealer did not provide a work order and she had to sign a power of attorney for the dealer to release the vehicle. The failure recurred with unintended acceleration up to 25 MPH, immediately after the brake pedal was released. The vehicle was not repaired. The insurance company did not deem the vehicle totaled. The manufacturer was not made aware of the failure. The failure mileage was approximately 41,000.

VEHICLE SPEED CONTROL — Filed 10/06/2021

The contact owns a 2018 Hyundai Sonata. The contact stated that while braking and pulling into a parking space, the vehicle reeved up, accelerated forward, and crashed into a wall. There were no reported injuries, or air bag deployment. The vehicle was towed to the local dealer where they were unable to duplicate the failure after a road test. The vehicle was not diagnosed or repaired. The manufacturer was notified of the failure. The failure mileage was approximately 20,000. Consumer stated crash was due to electronic malfunction. Auto will be assessed by Hyundai Corp case still open.

UNKNOWN OR OTHER — Filed 08/13/2021

1. Accelerator malfunctioned as I removed my foot to hit the brakes. The speed increased. When attempted to hit brakes, would not brake. The brake hardened up and car went through bank glass door and window. 2. It malfunctioned. 3. Vehicle is in the body shop. Will take to dealer when done 4. Police and insurance 5. No warnings

SEAT BELTS — Filed 03/25/2021

2018 HYUNDAI SONATA WAS IN MOTION, WITH A SPEED OF APPROXIMATELY 20 MILES PER HOUR, WHEN A VEHICLE IN FRONT OF THE HYUNDAI SONATA STOPPED SUDDENLY AND THE 2018 HYUNDAI SONATA REAR ENDED THE OTHER VEHICLE. THE 2018 HYUNDAI SONATA'S AIRBAGS DID NOT DEPLOY. DAYS PRIOR TO THE MOTOR VEHICLE ACCIDENT, THE THE OWNER DISCOVERED THE DRIVER'S SIDE SEATBELT WOULD NOT RETRACT TO CREATE TENSION AFTER INITIAL APPLICATION TO SECURE SEATBELT HOWEVER, TENSION OF THE SEATBELT WAS IDENTIFIED WITH APPLICATION OF THE BRAKES, WHILE LEANING FORWARD, AND WHILE 2018 HYUNDAI SONATA WAS IN MOTION. CONCERN IS THE FACT THE AIRBAG DID NOT DEPLOY APPROPRIATELY DURING A FRONT END COLLISION WHILE IN MOTION AT APPROXIMATELY 20 MILES PER HOUR; POSSIBLY RELATED TO NHTSA ACTION NUMBER EA19001, APRIL 19, 2019, REGARDING THE 'AIR BAG ACU ELECTRICAL OVERSTRESS' THAT IS CURRENTLY OPEN AND UNDER INVESTIGATION. SEE PICTURES ATTACHED.

POWER TRAIN,ELECTRICAL SYSTEM,ENGINE — Filed 02/24/2020

I WAS DRIVING MY CAR AT ABOUT 45MPH ON MY WAY TO WORK ON A HIGHWAY ROAD AND OUT OF NO WHERE IT JERKED AND THE CHECK ENGINE LIGHT STARTED FLASHING. CAR WOULD NOT ACCELERATE ABOVE 2,000 RPMS. WHEN THE CAR JERKED, IT WAS SO SUDDEN IT INJURED MY LOWER BACK. MY BACK HAS BEEN VERY SORE SINCE THIS INCIDENT. I THEN TOOK TO DEALER AND THEY SAID IT WAS A KNOWN ISSUE AND HYUNDAI HAD NOT RECALLED MY SPECIFIC CAR. DEALER WAS ABLE TO REPLICATE THE ISSUE. THE CLEARED THE CHECK ENGINE LIGHT AND SENT ME ON MY WAY. ONE MILE DOWN THE ROAD EXACT SAME THING HAPPENED. CAR IS CURRENTLY AT THEIR SHOP WITH NO ETA OF REPAIR.

UNKNOWN OR OTHER — Filed 01/28/2020

DRIVER STATES VEHICLE DECELERATED WHILE DRIVING, PULLED OFF THE INTERSTATE AND OVER TO SIDE OF THE ROAD VEHICLE CAUGHT FIRE IN ENGINE COMPARTMENT.

ELECTRICAL SYSTEM,ELECTRONIC STABILITY CONTROL (ESC),ENGINE — Filed 01/22/2020

THIS CAR HAS A MIND OF IT ON WHEN I TURN ON HEAT THE RADIO STATION GOES STATIC VERY BAD ENGINE LIGHT KEEP COMING ON GO TO DEALERSHIP THEY KEEP ON RESET INSTEAD OF FIXING IT YESTERDAY MY STARTER BURN OUT .JUST OUT THE BLUE WITH NO WARNING SIGN IT WAS GOING OUT