general problems of the 2020 Hyundai Sonata - part 2

The fuel tank under the backseat expanded forcing the backseat up and causing the muffler to scrape the ground. The expansion of the fuel tank could have exploded due to extreme pressure. Vandergriff Hyundai in arlington, TX has inspected the vehicle and confirmed component failures in the fuel system. The vehicle has been inspected and currently in the process of being repaired at the dealership. The check engine light was illuminated to warn of component failures approximately six weeks ago.

Summary: the gas tank on this vehicle blew up/expanded rapidly to the point it could have erupted into a gasoline vapor fireball, killing the occupants of the vehicle or others. According to two Hyundai dealers, a failure in a check valve and the vehicle ecu programming caused pressurized air from the engine to be pumped into the gas tank, causing it to expand to the point of explosively popping out all of the sheet metal under the back seat. One Hyundai dealer service technician described the vehicle as, quote, 'a ticking time bomb'. There was no check engine light or warning at the time of this explosive event, although one occurred later. Hyundai has not offered to repair this vehicle. Please note that this potentially deadly issue is already well known to Hyundai/kia. The Sonata has a sister vehicle from kia that is the same vehicle platform called the k5. Kia issued a service campaign to address this extremely dangerous issue in April (TSB: sc288 k5 (dl3a) April 2024) which reads in part: "the subject vehicles may experience fuel tank swelling due to an issue with the pcsv check valve, which results in pressurized air to flow into the fuel tank. " in addition, at last check an investigative reporter in charlotte, nc has identified numerous Hyundai and kia vehicles in which this has occurred. There's likely far more people who have already had this occur, and potentially thousands or hundreds of thousands of vehicles with this potentially deadly condition. (see: wsoctv. ***/news/local/kia-acknowledges-gas-tanks-swelling-suddenly-offers-free-fix) as stated above, Hyundai has not offered to fix my vehicle. Please immediately take steps to force the manufacturer to remedy this extremely dangerous condition for all affected owners before someone is injured or killed.

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.

While driving at about 45mph a warning flashed on my dash. I couldn't read it before it disappeared, but it was something about front collision. , contact dealer. The car immediately lost all power. Everything was still running, but I had no acceleration. I had to back down a busy road into a vacant lot. I had just come off of the highway when this happened, if I had still been driving on the highway, I would have been hit by a car from behind, since there was no warning at all. The car was towed to a Hyundai dealership. After a diagnosis, it was said to be the throttle body. I had to wait for the repair because the part was on back order. I was told that there was another car there waiting on the same part. I am afraid to drive the car now, even though the repair was made. I feel this is a safety hazard, and that someone could be injured or killed because of this issue with the car.

Been having an issue with a check engine light and a popping noise in the from the front of the vehicle for about two years. Took it to the dealership more than 3 times over that span and every time they discovered it was caused by something different. . During the July of 2024 while driving on the interstate a loud pop noise was made from the back and my children complain about the seat lifting…shortly after I went to get gas and a full tank was more gallons than usual 14 increased to 17g…. I once again took it to the dealer for the issue of the gas tank expansion and pop but found nothing. No more than a week later my car would hesitate to accelerate and progressively got worse. On 12/27/24 I took it to the dealer and they discovered my gas tank was expanded and was unsafe to drive leaving me without a vehicle. As of 1/04/2025 I still have no solution.

As the vehicle was at a complete stop and waiting for a chance to get in traffic, the car hestiated and would not respond to the depress of the gas pedal, for a second or two. . . Very strange indeed!. . . . Is it a transmission issue or something else. . . . The transmission shifts strange from the complete stop position. . . This happenes more than once! and one instance it actually jerked ( bucked) somehow. . . Concerned about this. . .

On Nov. 17 while driving app. 65 mph on the highway the car suddenly shut itself off. All of the dashboard lights lit up & the car would not restart. After 10 min. Of trying to restart the car, the car started again, & all the lights on the car disappeared. The following day, while waiting in the turning lane at a red light, the car sputtered & turned off. All the lights on the dashboard lit up & the car wouldn't start I had the car towed on Nov 18 202 to a Hyundai dealership. The dealership reported that there was an internal short with the abs module & the hydraulic module assembly was replaced. On, Nov 24, I was driving the car & the car stalled all the warning lights went back on. I had the car towed the dealership where it stayed until December 11 the dealership stated that they could not find anything wrong with the car. I picked up the car on Dec 11 & the car appeared to be working normally. However, on dec19, while stopped at a red light, the car began to shake back & forth at idle & the rpms started to go up despite my foot being on the brakes. The car behind me saw what was happening & helped me pull over to the side of the road. I had the car towed to the dealership yet again. The dealership stated that they were able to duplicate the issue on Dec 23, 2020. However, no fix was done to the car. The dealership claimed that the car was in a �relearn� process & it would need more time for the car to �relearn� how to drive again. Everything seemed okay after the Dec 23 incident until Feb 8 2021 when I tried to stop while in traffic & the brakes would not work at all. I narrowly avoided getting into a major accident & once again brought the car to the dealership. The dealership found that the master cylinder assembly was internally defective & was not holding pressure and as a result the brakes were not working. The vehicle was returned to me on Feb 11 2021.