What 87 owners told NHTSA about the 2024 Hyundai Tucson Fuel Cell

Subject: Urgent Drivability Concern – 2024 Hyundai Tucson (6/22 Incident) Vehicle: 2024 Hyundai Tucson Date of Incident: XXX Trip Details: [XXX] to [XXX] (~160+ miles) Summary of Issue: During a long-distance drive on XXX, the vehicle experienced severe and consistent drivability issues that created unsafe driving conditions. Symptoms Observed: •Severe loss of acceleration / stalling behavior throughout the entire trip •No check engine light illuminated at any time •When pressing the accelerator: oTachometer increased (RPMs rising) oVehicle speed decreased or failed to increase appropriately •Significant delay in acceleration, especially when: oMerging onto the interstate oPassing other vehicles •Cruise control behavior: oSeemed to manage acceleration more effectively than manual throttle oHowever, still exhibited slow response when additional acceleration was required •Auto Start/Stop system: oSystem automatically disabled itself oWould not allow reactivation during the trip Safety Concern: This condition made it difficult and unsafe to: •Merge into traffic •Maintain appropriate highway speeds •Execute passing maneuvers Dealer Visit (Near [XXX]): •Vehicle was inspected after sitting for a couple of hours •Dealer reported no issues found •However, the problem was persistent and clearly present during operation under driving conditions Took vehicle to a dealership in Raleigh and asked that they look at the fuel injectors. They determined that all 4 injectors were failing and replaced them under warranty. Concerned that Hyundai America has not issued a recall as driving the vehicle with this issue creates a serious safety concern that would lead to injury or loss of life INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11748709

While driving at approximately 70 mph on a highway under normal conditions, the vehicle experienced a sudden loss of engine power. A check engine light illuminated at the time of the failure, and the vehicle was unable to maintain normal acceleration or consistent speed. The loss of power created a hazardous situation in active traffic, as the vehicle could not safely maintain speed with surrounding vehicles. The vehicle was later inspected by an authorized dealership, which confirmed severe internal engine damage, including cylinder damage and engine misfire requiring major repair or replacement. No clear root cause has been provided. There were no prior warning signs or symptoms before the incident. WARNING SIGNS PRIOR TO FAILURE: NONE OBSERVED. The vehicle is available for inspection upon request. DEALER CONFIRMATION: YES. MANUFACTURER INSPECTION: UNKNOWN.

NHTSA ODI 11732364

Component: Engine/Powertrain/Electrical System Incident Description: I am reporting a recurring, life-threatening "Loss of Motive Power" (Dead Pedal) in a 2024 Hyundai Tucson (Alabama-built). On multiple occasions, the vehicle has failed to respond to throttle input during high-risk maneuvers, specifically while merging into 45+ MPH traffic. The vehicle "chugs" and stalls, refusing to exceed 15 MPH despite full accelerator depression. This defect leaves the vehicle and its occupants stranded and defenseless in the path of oncoming high-speed traffic. Technical Context: This vehicle is currently subject to NHTSA Recall 23V-526 (Hyundai Campaign 246) for electronic controller damage that can cause "CAN communication disruptions." I believe the "Dead Pedal" failure is a direct result of these communication disruptions between the engine and transmission control modules. Furthermore, Hyundai has issued TSB #24-AT-001H-1 for "Hesitation when accelerating," yet the authorized dealer (Ed Voyles Hyundai) has been unable to remedy the defect after 84 cumulative days out of service. Safety Risk: This is not a convenience issue; it is a critical safety failure. The unpredictable nature of the power loss makes it impossible to safely judge gaps in traffic. The vehicle effectively becomes a stationary object on active roadways without warning. Manufacturer Response: The manufacturer has been formally notified via certified legal counsel. Despite 79 consecutive days in the current repair attempt (since Jan 16, 2026), the manufacturer has failed to provide a fix or acknowledge the severity of the safety risk. An informal third-party evaluator attempted to dismiss the claim despite the vehicle's documented inability to maintain motive power. We are requesting that NHTSA investigate the adequacy of Recall 23V-526 and TSB #24-AT-001H-1, as these measures have failed to resolve this life-threatening "Dead Pedal" condition in my vehicle.

NHTSA ODI 11729169

My 2024 SEL hybrid has a very annoying acceleration delay after a full or partial stop. The delay has occurred many times. It is present no matter which mode the car is on. It is not a matter of slow acceleration, but a 1-2 second delay of anything happening after I press the pedal. this could be a safety issue when you're at a stop sign and you need to proceed and you can't go.

NHTSA ODI 11711658

My wife was slowly pulling into a parking spot, when at about 10ft from curb the car suddenly accelerated faster than she even thought the car even was capable of (the AWD likely helped). It hopped the curb and hit a tree. She backed it up to the parking spot (it acted normally) and had it towed to dealer. In hindsight, the car had been having a progressive amount and frequency of delay in normal acceleration, sometimes having a pause of up to second or two from pedal input to car response. We asked the dealer to check the EDR (event data recorder). The tech first said he didn't even know what that was, then that he checked with all his fellow techs and they didn't know either, then the story changed to the model not having an EDR. We politely told him which page in the Hyundai manual he can find it, and he refused to look, as did his boss. Car was transferred to a body shop, and disposition was to total the vehicle. While the body shop was still evaluating the car, we contacted a second dealer, who said they don't have a reader. I inspected the floormats before the car was towed, as that was an initial suspect, but it was locked in and clearly there was no obstruction. She was wearing tennis shoes and doesn't recall ever having an instance of hitting the wrong pedal in any vehicle. She thinks she was only coasting, not even touching the brake yet.

NHTSA ODI 11709963

On multiple occasions the vehicle has not transferred from EV to mechanical mode and has stalled out. Shutting the car and restarting it resolved the problem each time. Hyundai has not been able to find the fault after multiple trips to the dealership and no code is recorded or reported. I bought a code reader and the last time this occurred recorded a code. P1120 $07e8Pd I brought the car back into Hyundai and reported the code to- It was not saved in the car's memory. They have had the car for over 3 weeks now and repairs have not been completed.

NHTSA ODI 11665390