2020 HYUNDAI SONATA Unknown Or Other Problems
25 complaints about Unknown Or Other
High Severity Issue
This component has been associated with crashes, fires, or deaths.
This Problem Across All Years
All Unknown Or Other Complaints (25)
My 202 Hyundai Sonata is involved in the current hyundai fuel system recall. on 10/26/25 the fuel tank expanded and caused three explosive "boom" sounds inside the vehicle while I was driving with passengers. The backseat began heating and rising upward due to fuel tank swelling. The tank became pressurized, hissing, bubbling, and would not accept fuel. The vehicle became inoperable. The car has now been at hyundai of camelback since 10/27/25 (30 days). Hyndai Corporate has repeatedly delayed providing a remedy and keeps telling me they "need another week". I have received no repair plan, and no decision. This violates the requirement for a timely recall remedy. The defect caused structural damage and created a serious safety hazard. "
Coolant is leaking again after being fixed at a Hyundai dealer. If I don't fix it, my car will overheat and catch fire in the middle of a public road. My warranty has now expired, so I'll have to pay for the repairs myself. However, this problem is a design flaw, not related to the car's age or mileage. Hyundai should fix this problem. I'm not the only one; there are a lot of people complaining about this.
The ac blower keeps going out I looked it up and a lot of people are having the same problem my ac keep having to buy blowers and they last 1 week before they stop working and they are not cheap my blower keeps going out and my electric in my car keeps messing up when I try to put the ac up it goes up then goes down I don’t know what’s wrong but I looked it up and a lot of people have the same problem
My 2020 Hyundai Sonata SE (82931 miles at the time) has experienced repeated issues with the front passenger window. The window would get stuck while attempting to operate it, accompanied by a loud, crushing noise. Upon visiting the dealership, I was informed that the issue stemmed from the window regulator, which had failed internally and required replacement. Additionally, my girlfriend, who owns a 2020 Hyundai Sonata SEL with approximately 31,000 miles, is now facing the exact same problem with her vehicle’s front passenger window. After conducting research on online forums, I discovered that several other 2020 Hyundai Sonata owners are reporting similar issues with their window regulators. This suggests that the problem may not be isolated to just one or two vehicles but could point to a potential widespread defect. Although this issue primarily affects the operation of the window, it could lead to safety risks if the window gets stuck in an open position, exposing occupants to potential theft, weather elements, or other hazards. I am requesting the NHTSA investigate this matter to determine if the window regulator failure in 2020 Hyundai Sonata models is a systemic defect that warrants further action, such as a recall or manufacturer response. I am happy to provide additional information or documentation, such as repair invoices, dealership statements, or records of the issue. Thank you for addressing this concern.
I believe the transmission malfunctioned as I reached 60 MPH / 4000 RPMs on the highway when it suddenly did not want to accelerate past that. The more I stepped on the gas pedal, the more it slowed down. I attempted to use the paddle shifters to shift up or down, but I was unable to shift up and shifting down did not allow me to accelerate past 4000 RPMs. The flow of traffic was faster than I could keep up with, and not being able to accelerate made it unsafe to be on the highway. I had to pull over, and get off of the highway. I found that others have reported this same issue online with the same make/model/trim, but I have not had time to take it in to be looked at. No warning lamps, messages, or other symptoms prior to failure. I only noticed when I got on the highway and needed to reach speeds greater than 60 MPH. Turning the car off, waiting a bit, then starting it again seems to have resolved the issue, but I am still uneasy with this having happened so suddenly. I fear the issue may return in the future based on what I have read online. The car is available for inspection upon request.
Took a trip to Nashville so I left Memphis Saturday morning hole on the road heading to Nashville I was at least 30 minutes fork the city my car began to jerk very bad suddenly my file light came on so I stopped at a gas station the file light came on telling me I needed gas the had was on the E but my mileage to e said 117miles. So I was like ok that’s weird after I put gas in my car I got back on the road my gas hand went from full to half way and I was not even on the road for 40 minutes so as we get closer to Nashville my car starts jerking very bad I hear a noise that sounded like a bag or a piece of paper being crumbled up I turn around to find my rear seat up in the air I knew it was not normal at all looks like it was a lot of pressure for the frame of a car to stand up like that I definitely knew something was wrong when that happened I instantly started to smell gas very loud smell of gas I then start to do my research and I see Kia’s and Hyundais are dealing with gas tank expansions so at this point I am scared for my life I’m in my car and I’m dealing with a issue like this. I instantly call my dealership and schedule to have my car towed to the dealership out in Nashville. They called me that Monday confirming the gas take had expanded and caused a significant amount of floor damage to my vehicle I am currently waiting trying to see what is Hyundai going to do about this issue that is my only transportation and having to deal with this then find another way back home has been very stressful and just to know that I could have lost my life in that car is even more traumatic
Driving 55mph on highway car slows down and make a pop nose and back seat comes up and I start to smell gas
An independent service center advise us that the gas tank had expanded which could have put my family at risk if exploding or catched on fired. This happend on June 15th 2024 while driving, a sudden explosion coming from the back of the car was heard. Little after the explosion like sound we perceived as if air was coming through the back as if we had a window rolled down. When pulled to check, i notice that the back seat was popped up. No warning on the car was giving prior to the incident. Will take car to Hyundai dealership to have it inspect by them and have a solution.
UNKNOWN
A lot of these models have wind coming through the door making a whistling noise, it’s very distracting to drivers and multiple people complaining about it online.
Sunroof shattered/exploded for no known reason while driving. Resulted in glass falling towards cabin of vehicle as well as loud bang.
Hyundai updated the software for the display and made the font smaller which makes it difficult to read and a safety issue especially when driving at night. I contacted Hyundai and they say that if it is not in the owners manual there is nothing they can do. I have tried to explain to them it is a software issue that came about when their software engineers updated the software and it makes this a safety issue and they have no way to revert back to previous versions.
Paint on hood of car is peeling off, down to bare metal
The AC Fan in my car quit working. Took it to a repair shop where I was told that the AC Blower Motor went bad. The blower motor was drawing too much amps and caused the blower motor fuse to melt into the wiring harness for the blower motor along with melting several other fuses nearby including the fuse box. The cost to repair this correctly fixing and addressing all parts damaged was $5000. Because my vehicle is out of warranty due to mileage I contacted Hyundai who stated that I had to go and pay another diagnostic fee at a Hyundai Dealership to have them look at it. They continued to tell me that the vehicle was out of warranty but would not assist in providing information to get the issue resolved at no cost to me.
while driving to work on 05.20.2022 my sunroof exploded for no apparent reason. I called my insurance company and they told me to take it to my dealership. so I did.
- Shifter system malfunction - Unable to use the shift buttons - Received system error on dashboard that read, "Shifter malfunction! Service immediately." Visited two dealership, who saw a photo of the system error message. Vehicle was inspected by the dealership; however, no support could be given due to the dealership not having a code for the issue. - Dealership was made aware of the issue back in November 2021; however, first available appointment with technician was not until January 2022.
Driving on the Interstate at 65mph the car suddenly goes down to 5mph. Unwanted deceleration! At the same time the dash warning lights come on. Check engine and ABS. This happened 3 times now. 2 times on the Interstate in heavy traffic and once going 35mph on a back road. Miraculously we were able to pull over without any cars slamming into us. This unwanted deceleration happened on July 28, August 18 and Sept 13. Each time after pulling to a safe area we turned the engine off, waited a few minutes and turned it back on. Then resumed normal driving speed. Brought it to the dealer after each time. This shut down started after the car was only 4 months old with 2,983 miles on it.First time they said they couldn't find anything wrong and reset the computer, said if it happens again they will look into it more. The second time they replaced a Body Assy-Throttle and Gasket. The 3rd time they replaced the front wiring assembly control. I have all the repair paper work. We were driving playing Russian roulette wondering when it will happen again. With cars speeding around us we were lucky no one was close on our tail. This is an extremely dangerous situation. Each time it was beautiful sunny weather, two times heading to the beach, 3rd time heading to NH after 2 hrs of driving and one hour stopped, resumed driving for 20 min when it happened. No common denominator. I hope that this is not happening to others. I have reported this issue to Hyundai Motors America and they have offered me $500 and 60 days to release them from any liability or claim. Since I just got my car back finally Sept 20th, I certainly can't say my concerns have been resolved.
The automatic shut off. When the car is locked I can run it for a total of 20 minutes with auto start, when it's unlocked I can run it for a total of 60 minutes. Sometimes because of my job I need to auto start it and run it for longer to either warm up or cool down and it is unsafe to leave it unlocked. There should be an option for me to turn off the time limit and not have it reset every time I restart the car! When I'm shopping and I need to leave my dog inside for instance and it's 91 degrees outside, I should be able to lock my car and let it run for as long as I need to be in the store without worry it will shut off with him inside and suffocate him in the heat. This is another HUGE safety issue!
The Contact owns a 2020 Hyundai Sonata. The contact stated while driving 60 mph, the vehicle abruptly decelerated to 30 mph. The contact also stated that previously the windshield wipers failed and the driver’s side window failed to roll all the way up. The vehicle was towed to the dealer to be diagnosed. The mechanic was unable to retrieve a diagnostic trouble code. The contact stated that the dealer could repair the driver’s side window and windshield wipers. The manufacturer was contacted and informed of the failure. The failure mileage was 16,000.
Mileage: 16,000
THE VEHICLE'S FUEL GAUGE (TYPE C) DOES NOT ACCURATELY ADJUST FOR CHANGES IN THE AMOUNT OF GAS IN A TIMELY MANNER. IT NORMALLY TAKES 2-3 DAYS FOR THE GAUGE TO MOVE TO FULL TANK EVEN THOUGH IT IS FULL. SAME PROBLEM FROM 1/4 TO 1/2 TANK, ETC. FOR EXAMPLE, I NOTICED THE PANEL SAID I HAD 11 MILES TO EMPTY ON FRIDAY. THE GAS GAUGE SHOWED OTHERWISE. I WASN'T NEAR MY USUAL FILL STATION, SO I PUT 5 GALLONS OF GAS IN THE CAR. IT IS NOW WEDNESDAY (5 DAYS LATER). THE GAS GAUGE MOVED SLIGHTLY YESTERDAY TO ALMOST 1/4 TANK, BUT THE FUEL TANK WARNING WENT FROM 11 TO 0 MILES LEFT TO EMPTY (SEE ATTACHMENT). I DROVE ON THE HIGHWAY EACH DAY AND IN THE CITY. I PURCHASED THIS CAR JULY 2020 WITH A FULL TANK. THIS PROBLEM BECAME EVIDENT IN AUG 2020. AFTER REFILLING THE TANK, THE READER SHOWED 111 MILES TO EMPTY. I INFORMED HYUNDAI AGENT OF THE ISSUE, WHO HAD NO IDEA WHY THIS WAS HAPPENING. THE GUAGE AND FUEL TANK READER FINALLY ADJUSTED AFTER ABOUT 3 DAYS. I HAD 449 MILES ON THE CAR AT THAT TIME. I NOW HAVE OVER 4,000 WITH SAME PROBLEM. APPARENTLY, SOMETHING IS FAULTY, BUT I DON'T KNOW WHAT. AUTO DEALER IS BAFFLED. THIS ISSUE COULD RESULT IN A REAL FUEL SHORTAGE WHILE TRAVELING WITH NO GAS STATION NEARBY.
Mileage: 449
PUSHED THE PARK BUTTON, SHOWED P ON THE DASH INDICATOR, DOORS THEN UNLOCKED. WHEN EXITED VEHICLE IT BEGAN ROLLING BACKWARD, PARK HAD NOT ENGAGED SLIGHT HILL ONLY. THIS HAS HAPPENED REPEATEDLY. PUSHED BUTTON TO PLACE THE CAR INTO REVERSE AND THE VEHICLE WOULD NOT ENGAGE OR GO ANYWHERE.
Mileage: 500
ENGINE BLOCK BECAME INFESTED WITH RATS/MICE OVERNIGHT. I BELIEVE THIS WAS THE RESULT OF SOY-BASED COMPONENTS USED BY HYUNDAI. NO OTHER CARS ON MY BLOCK HAD THIS PROBLEM (I WAS ABLE TO SURVEY THE VEHICLE OWNERS BECAUSE WE ALL WERE THERE WAITING FOR STREET CLEANING TO OCCUR.) IT SEEMS OBVIOUS THAT THE RATS/MICE WERE ATTRACTED BY THE MATERIALS USED BY HYUNDAI AND ANECDOTAL REPORTS SUGGEST THIS IS A CHRONIC PROBLEM AMONG MANY CAR MANUFACTURERS, BUT ESPECIALLY ONES THAT USE SOY BASED COMPONENTS SUCH AS HYUNDAI, LAND ROVER, AND HONDA.
Mileage: 9,998
THE CAR WHILE I'M DRIVING SOMETIMES THE CAR IS UNSTABLE ALSO WHEN I TURN ON THE CAR AND I PREPARE TO PUT IT ON DRIVE THE CAR APPLY THE EMERGENCY BRAKES BY ITSELF. THE EMERGENCY BRAKE LIGHT IS ON AND THERE IS NO WAY TO REMOVE IT, I HAVE TO TURN THE CAR ON AND OFF CONTINUALLY UNTIL FINALLY THE CAR REMOVES THE BRAKES. I WAS DRIVING ON THE HIGHWAY AND ON THE STREET AND WHILE I WAS DOING SO THE CAR PUT ON THE BRAKES BY ITSELF. ONE TO TWO MONTHS AGO I TOOK THE CAR TO THE DEALER AND I TOLD THEM ABOUT IT BUT THEY SAID THAT THE CARE NEEDS 2 UPDATES, APPARENTLY THE CAR HAS TWO RECALLS. 6 HOURS LATER AFTER THE UPDATE THE CARE WASN'T WORKING PROPERLY AND THEY KEPT THE CAR FOR 3 TO 4 DAYS, I GOT A LONER BY THEN. LAST WEEK WEDNESDAY 08/05/2020 I TOOK THE CAR AGAIN TO REPORT THE PROBLEM AND I WAS TOLD THE CARE WOULD BE READY IN 5 HOURS BUT AFTER 5 HOURS IT WASN'T. SINCE I DIDN'T FEEL SAFE IN THE CAR I TOLD THEM TO KEEP THE CAR AND GIVE ME A LOANER BECAUSE THE CAR IS GOING TO TAKE ONE WEEK TO FIX BECAUSE THEY HAVE TO ORDER PARTS, THEY WANT TO KEEP THE CAR BUT THEY DIDN'T WANT TO GIVE ME A LOANER. I CONTACT HYUNDAI CORPORATE TO REPORT THIS INCIDENT BECAUSE IT IS TWICE ALREADY, AND I WAS TOLD THAT SOMEONE WOULD BE IN CONTACT WITH ME IN THE NEXT 48 HOURS. I MISSED THE CALL AND I HAVE BEEN TRYING TO CALL TO GET IN CONTACT WITH THEM AGAIN TO FIX THE PROBLEM BUT EVERY TIME I CALL THEY COME WITH ANOTHER EXCUSE. THE CASE MANAGER IN CHARGE OF THE CASE IS GARRISON AND THE CASE NUMBER 17216875.
Mileage: 650
REAR DOORS RETAIN WATER EVERY TIME IT RAINS. WHEN YOU OPEN THE REAR DOORS WATER DRAINS OUT OF THE CAR. BROUGHT CAR TO HYUNDAI DEALERSHIP WHO VERIFIED THE PROBLEM AND CONFIRMED THE PROBLEM WITH OTHER NEW CARS ON THEIR LOT, ON APRIL 21, 2020. DEALERSHIP CONTACTED HYUNDAI CORPORATE FOR GUIDANCE AND THERE HAS BEEN NO RESPONSE TO DATE. *TR
Mileage: 520
WHEN IT RAINS WATER GETS INSIDE THE DOORS WHILE PARKED. ESPECIALLY THE BACK DOORS. IF IT RAINS HARD A CUP FULL OF WATER WILL COME OUT THE DOOR UPON OPENING. I'VE BEEN TOLD IT'S A DESIGN FLAW. I'VE HAD IT LOOKED AT TWICE AND IT'S STILL NOT FIXED. CUSTOMER SERVICE CAN'T HAVE SOMEONE COME OUT AND LOOK AND IT BECAUSE OF THE VIRUS, SO THERE'S NOTHING THAT THEY CAN DO.
Mileage: 200