2024 HYUNDAI SONATA Power Train Problems

The contact owns a 2024 Hyundai Sonata. The contact stated that while attempting to accelerate to overtake another vehicle at approximately 60 MPH, the vehicle unintendedly decelerated to approximately 20 MPH instead. The contact pulled over to the side of the road, turned off the vehicle for approximately 20 minutes, before restarting and continuing to drive. There were no warning lights illuminated. The failure had occurred three times. The vehicle was taken to a certified mechanic, who diagnosed that the transfer case had failed and referred the contact to the dealer for assistance. The vehicle was taken to the dealer, who was unable to determine the cause of failure. The vehicle was repaired. The manufacturer was made aware of the failure. The failure mileage was approximately 16,500.

After a dealer-installed software update on my 2024 Hyundai Sonata sel awd, the car began jerking during acceleration and shifting. This happens at low and moderate speeds and creates an unsafe hesitation, especially in traffic. This issue did not exist before the update. I believe the software update affected the transmission or engine control calibration. The dealership has not resolved the issue, and it poses a safety concern. Please investigate whether this is linked to a faulty update affecting other Sonata vehicles.

My car tends to jerk very hard two to three times on cold start up and I’ve read that the previous years have had this issue. They are still the same mechanically so I do not know why my year does not have a recall for it

Vehicle suddenly accelerated after pulling out of store parking lot at low speed into side street behind vehicle stopped at light (less than a car length in front) while pressing hard on brake. Vehicle lurched forward incrementally during the braking process, but vehicle kept accelerating causing vehicle to hit stopped vehicle numerous times before vehicle engine was finally turned off. Driver of both vehicles could have been seriously hurt. Vehicle was driven home after this incident without incident but has only been driven out of garage and onto and off towing truck. Car has not been inspected except for damage to vehicle and is currently awaiting insurance rep inspection at vehicle repair facility. Once damage is repaired car will be towed to dealership for inspection. Because of the short distance vehicle traveled no warning lamps/messages were noted.

I have gone 3 times to dealer because speedometer was off. They confirmed that the speedometer was off but they couldn't do anything about it. They told me that for this car, there is no VSS and the speedometer gets the speed from the navigation system. The navigation system is obviously glitching which is causing this. I am not the only person experiencing this. This has to be taken care of and taken seriously