2020 Hyundai Sonata: wrong fuel gauge reading

Filed Jun 22, 2026 · Body, Fuel system · 89,000 miles · AZ

The contact owns a 2020 Hyundai Sonata. The contact stated that while driving at an undisclosed speed with the family inside the vehicle, a strong gasoline odor was inside the cabin of the vehicle. The contact stated that the fuel gauge was lowering quickly. Upon exiting the vehicle, the contact became aware of gasoline gushing heavily out of the vehicle onto the ground. Two months prior to the failure, the vehicle was taken to an authorized dealer due to an abnormal sound coming from the rear of the vehicle. The contact received notification of the federal safety agency Campaign Number: 25V796000 (Fuel System, Gasoline); however, the recall repair was not performed because the part for the recall repair was not yet available. The vehicle was towed to a dealer where it was determined that the gas valve was not properly fixed. The abnormal sound in the rear of the vehicle was due to the fuel expansion, which caused the tank to rupture and melt. The melting caused the fuel pump to expand and melt, causing structural damage to the body of the vehicle. The structural expansion caused the rear passenger seats to raise up. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was 89,000.

Filed May 8, 2026 · Engine, Fuel system · 80,000 miles · MD

The contact owns a 2020 Hyundai Sonata. The contact stated that the fuel failed to go into the tank. The seat failed to move. The engine light illuminated. The vehicle stalled. While driving, the fuel gauge went from full to empty. The contact received the federal safety agency Campaign Number: 25V796000 (Fuel System, Gasoline) after the failure. The vehicle was towed to the local where it was diagnosed that the fuel tank had expanded. The vehicle was repaired approximately eight months later. The contact called another local dealer. Ourisman Hyundai Bowie, 2404 Crain Hwy A, Bowie, MD 20716, who was unable to schedule an appointment. The manufacturer instructed the dealer to keep the vehicle due to it being a fire risk. The manufacturer was contacted regarding a buyback. The failure mileage was approximately 80,000.

Filed Feb 20, 2026 · Engine, Fuel system · FL

On 2/19/2026 while driving, my 2020 Hyundai Sonata Limited 1.6T began making several loud explosive / popping sounds. At the same time, the fuel gauge on the display screen appeared to rapidly drop, as if the vehicle was losing gas. Immediately following this, the vehicle began to hesitate and lose power while accelerating. The hesitation felt like the engine was misfiring or struggling to maintain consistent performance. There were multiple explosive sounds before and during the hesitation. This created a major safety concern while driving and the vehicle underwent an inspection at Hyundai in Deland, FL. The service department was brief and stated they needed to keep the vehicle for repair for an unknown amount of time as the fuel tank expanded. No further information was provided at that time.

Filed Apr 7, 2025 · Fuel system, Seats · NJ

My wife and son experienced a terrible situation on the way home from training. They had to stop at the nearest gas station due to the vehicle showing extremely low gas in the tank during a short drive home. The fuel gauge initially showed about half a tank but drastically dropped on the way home. They stopped at a gas station to add fuel but during the process, fuel starting spewing out of the tank. The vehicle was scheduled to be dropped off at a later date for an open recall (service campaign 9B1). I called the dealership and told them I needed to get the vehicle in right away due to the incident. After bringing the vehicle to hyundai, they told me that the fuel tank exploded causing the tank to swell all the way around. Because the tank is located under the rear seat, we constantly heard air coming in due to the rear seat not seating properly. The check engine also was on and we smelled fuel while driving the vehicle. Hyundai representatives has been avoiding my calls to the point where I had to go in person for an update. Apparently, a district manager had to come inspect the vehicle to advise the dealership how to write up the request to send to corporate.

Filed Nov 27, 2024 · Fuel system · SC

What component or system failed or malfunctioned, and is it available for inspection upon request? The Fuel Tank expanded, was leaking gas from the gas tank opening. The expansion of the tank caused the metal plates/panel under the back seat to popup, where my child sits. Which caused a gap in the door. ir seepage from the back seat passenger door to where the fuel was leaking out the gas tank and also the fuel gauge on the dash was fluctuating. People on the highway was flagging me to let me know fuel was leaking. The fire department had to come and clear it. How was your safety or the safety of others put at risk? My child and I could have been seriously injured or killed. As well as people on the highway. It could have exploded. You can smell the gas in the car. The gas was coming out the gas tank on the side. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes, it was confirmed by Hyundai of North Charleston 8485 Rivers Avenue, North Charleston SC, 29406 and it was also checked by the insurance adjustor. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? It was inspected by the Insurance representatives State Farm Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? No I took it into the dealer and they said it was fixed and it did not fix the gas coming out the tank. And the same issue happened again on [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 13, 2024 · Fuel system · FL

I was driving back from Atlanta, GA to Pensacola, FL when we noticed our fuel level dropping significantly. We stopped in West Point, GA to see what was going on. We turned the car off and back on after 3 minutes and car made a weird vibration. Then the fuel level was rising back to normal but my wife was in the backseat with our [XXX] and she noticed the seat was rising and creating a lot of heat. We pulled over again and noticed it wasn't going down. Luckily there was a mechanic at this gas station and he informed us that the fuel tank expanded and to NOT drive the vehicle. We we're driving alongside my parents so we got in their car and drove back to Pensacola to get a truck and tow attachment cause a tow truck would've costed us $2,500 to tow back to Pensacola. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 11, 2024 · Fuel system · MD

The component that failed is the fuel tank system. While driving, the fuel tank expanded, causing significant damage to the rear section of the vehicle. This issue resulted in the rear seat rising up, and the bottom rear seat cushion detaching from its securing clamps. The check engine light came on, and gas started leaking from the fuel cap. The fuel tank has moved upward by about 3 to 5 inches, no longer resting on the factory fuel tank straps. The sheet metal underneath the rear seat was crumpled, and the fuel pump access cover bent. The vehicle is currently at College Park Hyundai and is available for inspection upon request. My safety and the safety of my children were significantly compromised. The loud popping noise startled us, and the fact that the rear seat lifted and detached posed a serious risk to the passengers in the back seat. Additionally, the gas leak created a fire and explosion hazard, putting all occupants of the vehicle and other drivers on the road at serious risk. This incident potentially violates the Fuel System Integrity (49 CFR 571.301) regulation, which ensures that a vehicle's fuel system is designed to prevent leaks and fire hazards. Moreover, the unexpected movement and detachment of the rear seat could be a breach of Occupant Protection (49 CFR 571.207 and 571.208), which govern the safety of seating systems and occupant crash protection. The issue has been confirmed by the service center at College Park Hyundai, where the vehicle is currently being inspected and evaluated. The vehicle is being inspected by the manufacturer’s authorized service center at College Park Hyundai. It has not yet been inspected by police or insurance representatives at this time. The check engine light came on immediately after the loud popping noise and the detachment of the rear seat cushion. Additionally, the gas gauge suddenly dropped to empty after the incident, even though the tank was not empty prior to the malfunction.

Filed Aug 31, 2024 · Fuel system · FL

(August 29th) My girlfriend and I were driving in my 2020 Sonata, when the check engine light turned on and my gas gauge dropped from being full to then only half way. About an hour later, driving back home we heard a loud pop as if something exploded. Next day, I took my car to the Autonation Hyundai dealership and after taking a look at my car they quoted me about $6,000 to get my fuel tank and charcoal canister replaced. Our safety was put at risk due to the fact that had the damage been any worse, it could have caused the car to possibly explode or give out while driving on the highway, and in turn would put many more lives at risk.

Filed Jun 12, 2024 · Electrical, Engine · FL

I was driving on the interstate when I heard a click from the back of the car. The gas gauge started to move downward as if I was losing gasoline. It eventually stopped and started moving back up, past where it was when it started decreasing. A little bit later the check engine light came on and the car started driving very sluggishly. I took the car into the Hyundai dealer and they found that the backseat was clicked out of place and a sensor was unplugged. This issue has since occurred multiple times. The back seat will pop out of place, the gas gauge will move beyond the gas that is in the tank, and finally the check engine light will come on and reduce the performance of the vehicle. The gas tank appears to be swelling and pushing up against the back seat which is causing it to pop. I had my girlfriend drive the car while I sat in the backseat and I could actually feeling something moving underneath the backseat. I have since gotten in contact with other sonata owners who have had the same thing happen with their vehicles. In other cases the backseat has exploded and flown completely off of the gas tank. I am very nervous to drive my car and think Hyundai should recall these vehicles before someone gets hurt.

Filed Apr 28, 2021 · Electrical · 449 miles · VA

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.