2021 Hyundai Santa Fe: check engine light

Filed Nov 1, 2026 · Driver assistance, Fuel system · FL

My 2021 Hyundai Santa Fe SE (VIN: [XXX]), with approximately 93,000 miles, has repeatedly experienced a dangerous loss of acceleration while driving at highway speeds of approximately 60 mph. When I press the gas pedal, the vehicle fails to accelerate, making it difficult to merge, pass, or respond safely to traffic. The vehicle does not suddenly slow down, but it will not increase speed when needed. This creates a serious safety risk to me and other motorists. The problem occurs without a check-engine light or advance warning. I have noticed abnormal behavior involving the Idle Stop & Go “A” indicator, which changes between orange and white. Coconut Creek Hyundai, an authorized Hyundai dealership, has inspected the vehicle multiple times. The dealership initially replaced the battery, then diagnosed and replaced the high-pressure fuel pump. The pump was replaced a second time due to a reported issue with the replacement. Software updates or resets were also performed. Despite these repairs, the original acceleration problem continued. The dealership has now diagnosed all four fuel injectors as severely clogged or defective and recommends replacing them. The service advisor stated in writing that the high-pressure fuel pump failure caused the injectors to fail. However, the dealership has not explained why this damage was not identified during earlier repairs or provided assurance that replacing the injectors will resolve the acceleration problem. Hyundai Motor America has been contacted regarding the repairs. The vehicle and dealership service records are available for inspection upon request. Availability of previously removed parts must be confirmed with the dealership. I request that the federal safety agency investigate this recurring highway acceleration failure as a potential vehicle safety defect. Multiple repair attempts have failed to resolve a condition that could result in a serious accident. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Oct 12, 2026 · Transmission · TX

On September 20, 2026, my 2021 Hyundai Santa Fe Calligraphy suffered sluggish acceleration while operating on a public roadway due to an internal dual-clutch transmission (DCT) failure. The Malfunction indicator light illuminated, and a diagnostic scan revealed stored history code P1C2D03, indicating a total breakdown of the high-pressure electric pump assembly. As of September 21, 2026 the vehicle is currently grounded at an authorized Hyundai dealership under an approved factory warranty repair Prior Authorization (PA) request. However the dealership has issued a written admission of "NO ETA" because the replacement transmission components are on an indefinite national backordered and are no longer being manufactured . Because the vehicle cannot be repaired in a reasonable timeframe due to a severe factory design defect , it remains unresolved.

Filed Jun 29, 2026 · Transmission · 78,000 miles · UT

The contact owns a 2021 Hyundai Santa Fe. The contact stated that while driving approximately 5-30 MPH, the transmission failed to shift properly, and the vehicle lost motive power. The engine warning light was illuminated. The contact stated that the failure was a recurring failure. The contact stated that the vehicle was repaired under the federal safety agency Campaign Number: 22V746000 (Power Train); however, the failure persisted. The dealer was contacted. The manufacturer was made aware of the failure. The failure mileage was approximately 78,000.

Filed Jun 24, 2026 · Acceleration, Engine · SC

My check engine light came on, and my car was also feeling "sluggish" and slow to accelerate. I scheduled a service appointment at my local dealer 4 days later. At the appointment, the technician stated everything checked out okay and the check engine light was likely an "anomaly" or "outlier" but otherwise nothing to be concerned about since everything checked out "okay" and no problems were identified during their test drive. However, that very afternoon, I was driving down the interstate, where the posted speed limit is 70mph, when my check engine light came on again and suddenly lost power, drastically reducing my speed and could not accelerate faster than 39mph. Luckily, the interstate was not busy at the time (about 10:30-11:00 a.m. Saturday morning) and there were only less than 4 cars behind me that were able to easily switch lanes and pass me. I moved over to the shoulder to a complete stop and restarted my car. My check engine light remained illuminated and was still slow to accelerate and "sluggish" but was able to (slowly) reach interstate speed (60-70mph) until I reached an acceptable exit and safely made it to my destination. I have since used roadside assistance to tow the vehicle from my home to the the same dealership for inspection and service (again).

Filed Apr 14, 2026 · Engine, Transmission · MA

First instance at 50-55 mph the transmission violently shook the car when downshifting to accelerate on multiple occasions. Dealership diagnosed the problem as a faulty transmission and replaced it at 44064 miles on March 18, 2025. Second time the car failed to accelerate when merging into traffic while the engine revved very high. Again it was taken to the dealership and the diagnosis was faulty transmission. A second transmission was in stalled at 51331 miles. Second transmission began downshifting hard upon accelerating at highway speeds. Retuned to dealership and diagnoses was faulty fuel injectors and all four were replaced on April 7 at 52960 miles. On April 10, 2026 the car displayed a check engine light after the car began shuttering at highway speeds and was immediately returned to dealership where it’s pending a diagnoses. Failure to safely accelerate when merging make this vehicle a safety risk.

Filed Jan 8, 2026 · Transmission · 99,700 miles · NC

The contact owns a 2021 Hyundai Santa Fe. The contact stated that while driving approximately 20 MPH, the vehicle experienced hard shifting while attempting to change gears, and the vehicle hesitated, and the check engine warning light illuminated. The vehicle was taken to an independent mechanic, but was not diagnosed or repaired; however, DTC: P1C2D03 was retrieved. The vehicle was then taken to a dealer, where the same diagnostic trouble code was confirmed. The dealer diagnosed that the transmission had failed and needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure, and a case was opened. The approximate failure mileage was 99,700.

Filed Jan 6, 2026 · Engine · NC

Car misfiring symptoms like rough or shaky idle, hesitation and loss of power during acceleration, stumbling, unusual popping/backfiring noises, poor fuel economy, and a lit Check Engine Light. Felt vibrations / heard sputtering sounds, as if the engine skipped a beat, often becoming more noticeable under load or when accelerating. Sometimes, the issue goes away after restarting the engine.

Filed Oct 17, 2025 · Transmission · FL

The transmission in my 2021 Hyundai Santa Fe has failed multiple times. The first failure occurred within the first two years of owning the vehicle. The car began jerking, hesitating, and struggling to accelerate, and the check engine light came on. The dealership confirmed a transmission issue and replaced the transmission under warranty. After that replacement, the same symptoms returned, and the transmission had to be replaced a second time, again under warranty. The most recent transmission replacement was only a few weeks ago, and the same symptoms are already returning — the vehicle hesitates, jerks, and occasionally loses power when trying to accelerate. These problems create serious safety concerns, especially when merging onto highways or crossing intersections. The hesitation and loss of power make it unpredictable and unsafe to drive. I have two young children who ride in car seats, and I no longer feel confident that this vehicle is safe for my family. Hyundai service employees have acknowledged that this is a known, recurring issue with this model’s transmission design. However, no permanent fix or recall has been issued, and I have been told to continue replacing the transmission under warranty until the coverage runs out. This approach does not address the underlying safety defect. The issue has been confirmed by Hyundai dealerships multiple times. The check engine light has come on before each failure. I am reporting this because repeated transmission failures that cause hesitation and power loss are a clear safety risk, and Hyundai has not provided a lasting solution.

Filed Jul 3, 2024 · Engine · 67,000 miles · TX

The contact owns a 2021 Hyundai Santa Fe. The contact stated while driving at an undisclosed speed, the vehicle unexpectedly shifted to neutral(N). The contact pulled over to the side of the road and attempted to restart the vehicle; however, the vehicle failed to start with the check engine warning light illuminated. The vehicle was towed to a dealer and was diagnosed with engine failure. The contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was opened. The failure mileage was approximately 67,000.

Filed Mar 21, 2023 · FL

Unknown vigorous shaking in rear of vehicle check engine light on. Stopped after turning car off and restarting. Hyundai found no causes and no codes when inspected for issue.

Filed Feb 2, 2023 · Transmission · 13,483 miles · LA

The contact owns a 2021 Hyundai Santa Fe. The contact stated while driving at an undisclosed speed, the vehicle was stalling with the transmission, check engine, and other unknown warning lights illuminated. The vehicle was taken to a local dealer on two occasions; however, the failure could not be duplicated. The contact stated that the failure recurred on several occasions. The vehicle was then taken back to the dealer, where it remained awaiting parts for the repair. The contact received notification of the federal safety agency Campaign Number: 22V746000 (Power Train). The manufacturer was made aware of the failure. The failure mileage was 13,483.

Filed Jan 31, 2023 · Acceleration, Engine · AZ

On January 26th, 2023 at 9:57am the vehicle was unable to shift into reverse, drive, or neutral. The vehicle's system sent automatic messages indicating to have the transmission control system checked. We had the vehicle towed to a Hyundai dealer to be serviced. The dealership advised they performed a software update and that nothing else needed to be done. Then on January 30th, 2023 at 7:44pm the vehicle's check engine light came on and the vehicles system sent us another notification to our phone and email that there was a transmission control system issue. The vehicle shakes abruptly when accelerating after a stop. I have photos of the warning messages as well as video of the car shaking.