2021 Hyundai Sonata

Transmission replaced twice and all of them continue to fail. Several Hyundai service centers are unable to determine the cause and are only able to update/relearn and replace whenever they are able to replicate the issue. The issue is that at a cold start, the car makes a popping sound, jerks and shakes. The car hesitates to accelerate. You can hear the noise of acceleration but RPM does not go past 3 and MPH doesn't go past 30mph. I'm unable to upload docs because of the upload limit. If there's another way to send docs, please let me know

The vehicle has experienced repeated transmission and Electronic Oil Pump (EOP) failures resulting in loss of propulsion, loss of acceleration, and transmission-related malfunctions. The vehicle currently has approximately 69,000 miles. On September 3, 2022, the vehicle lost propulsion while traveling approximately 31 MPH in traffic and would not respond normally to accelerator input. This created a dangerous situation and increased the risk of a collision. On the same date, while backing out of a parking space, the vehicle displayed a "Shifter System Malfunction" warning message and unexpectedly stopped while in reverse. The vehicle had to be powered off before it would operate again. Following these incidents, the vehicle was towed to a Hyundai dealership and the transmission was replaced in September 2022. Despite the transmission replacement, the vehicle continued experiencing issues involving the same system. The Electronic Oil Pump (EOP) was replaced in 2023 and again in 2024 due to recurring transmission-related concerns and diagnostic codes. In 2026, the check engine light returned and the vehicle was again diagnosed with a transmission-related failure. The dealership determined that the transmission requires replacement for a second time despite the previous transmission replacement and two separate EOP replacements. Internally, Hyundai has since revised its repair guidance for this condition, suggesting that prior repair procedures may not have fully addressed the underlying defect. The repeated failures of the transmission and EOP system despite multiple repairs suggest an underlying defect that has not been corrected. These failures create a significant safety risk because the vehicle can unexpectedly lose propulsion or fail to accelerate while operating in traffic. The vehicle is available for inspection upon request.

Vehicle suddenly lost heat in 30 degree weather. No warnings, check engine light, or temperature gauge indicators came on. Lucky made it to a parts store and found out I was extremely low on coolant. Bought coolant and put it in. Made it back to the house and was immediately low again. No visible leaking. Oil was completely fine (1 gallon of coolant would have have left some kind indicator). Realized it was more than likely the ehrs. If this happened during the summer, my engine could have blown due to a poor design causing a major accident.

I own a 2021 Hyundai Sonata 1.6T, which has an open NHTSA safety recall (25V796000) related to fuel tank pressurization and fire risk. I brought the vehicle to an authorized Hyundai dealership due to a check engine light, reduced performance, and DTC P14EE, which aligns with the recall condition. The dealership refused to treat the concern as recall-related unless I paid a diagnostic fee and later attempted to reclassify the issue as a customer-pay fuel pump repair. During this visit, the dealership replaced a fuel system sensor without my authorization, which I did not approve or consent to. The dealership has not provided documented test results explaining how the recall condition was ruled out and has not documented recall inspection on the repair order. I expressed that I do not feel safe driving the vehicle due to the fuel system recall and drivability issues. The dealership also refused to provide alternate transportation. I am concerned the recall is not being handled in compliance with NHTSA requirements and that unauthorized repairs were performed while attempting to shift a recall-related condition to the customer. I am requesting review of recall handling and dealer compliance.

The contact owns a 2021 Hyundai Sonata. The contact stated that while driving at 30 MPH and depressing the accelerator pedal, the vehicle failed to respond and lost power. The vehicle was coasted over to the right side of the road, turned off, restarted, and returned to normal functionality. An independent mechanic was contacted. The vehicle was taken to an independent mechanic to be diagnosed; however, the diagnosis was unknown. The vehicle was not repaired. The contact related the failure to NHTSA Campaign Number: 22V746000 (POWER TRAIN); however, the VIN was not included in the recall. The manufacturer was not notified of the failure. The failure mileage was 35,000.

2021 Hyundai Sonata with approximately 39,000 miles. On [XXX], the dashboard displayed the following message "Shifter system malfunction! Service immediately" When the warning appeared, the vehicle shifter button would not function, creating a traffic safety risk. History: Dealer service history shows the transmission was replaced on the vehicle under warranty on 08/30/2021 with 2,212 miles with no campaign/recall issued. Dealer states there is no recall campaign on this vehicles specific VIN # and NHTSA currently shows no open recalls for this vehicle. However, Hyundai advertises an 8-Speed DCT Safety Recall for the same year, make and model, and describes this identical issue, but has left this vehicle's VIN# out of scope for this recall, which is continuing to demonstrate the same issues. Current dealer/manufacturer response: On 9/4/2025, the dealer declined warranty or recall repair unless the fault was active on their diagnostic scan at the moment the scan was performed. A photo was provided to the mechanics of the dashboard showing the transmission service warning, with current mileage. The dealer advised there were no diagnostic log history showing the transmission error code even with photographic proof and attempted to return the vehicle to me. I have rejected the return of the vehicle and advised that this needs to be escalated, because if logs are not appearing, this is even a bigger cause for concern and that the vehicle is a safety hazard. Concern: Because this vehicle required an early transmission replacement and is now exhibiting new transmission/shifter warnings, I am concerned the failure relates to the known transmission/shifter recall on this model and that the recall scope and/or remedy is incomplete for the affected vehicles including my vin #. It is also possible the dealership is attempting to run out the warranty which expires in 3 months. Vehicle, photo of the warning, and service records are available for inspection. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (

After initial startup and drive for a short time, I come to a stop. Then after vehicle doesn’t want to accelerate as it normally would. Vehicle struggles to gain speed but, the engine revs excessively. I pull off the road and come to a stop and try to accelerate again and the same thing happens. I shut the vehicle off and wait a few minutes,then restart and the vehicle accelerates normally again. There were no check engine lights the when this has happened.