2021 Hyundai Santa Fe: sudden loss of power

Filed Nov 1, 2026 · Engine, Fuel system · NJ

For approximately the past year, my 2021 Hyundai Santa Fe, currently with about 23,000 miles, has experienced intermittent engine and fuel-system problems. During start-up, the vehicle sometimes makes an abnormal rattling/cranking noise, followed by noticeable engine and vehicle vibration. Warning lights may appear, and on some occasions the engine does not start successfully on the first attempt. When it does start, it may initially run rough. The vehicle has also stalled intermittently and has had repeated incidents where pressing the accelerator produced little to no engine response or acceleration. This creates a serious safety concern because the vehicle may unexpectedly stall, lose power, or fail to accelerate when needed while driving. The vehicle has been at an authorized Hyundai dealership for more than one month. The dealership has been working with Hyundai Tech Line and has replaced or evaluated the low-pressure fuel pump, high-pressure fuel injector, high-pressure fuel pump, MPI/port fuel injector, and valve cover. The latest recommendation is to drain, clean, and refill the fuel tank. Despite these repair attempts, the root cause has not been clearly identified or permanently resolved. I am concerned that the repair process has become trial and error, with additional components being replaced while the underlying safety-related issue remains unresolved. I am also being asked to pay out-of-pocket for some of these unsuccessful repair attempts. The vehicle is currently at the Hyundai dealership and is available for inspection if needed.

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 May 11, 2026 · Engine, Fuel system · FL

My 2021 Hyundai Santa Fe (VIN [XXX] ) is experiencing severe engine instability, including rough idling, hesitation upon acceleration, and intermittent stalling. These symptoms align with TSB 26-FL-001H regarding defective GDI fuel injectors. The vehicle has stalled in traffic, creating an immediate risk of a rear-end collision. Despite being within the 100,000-mile Powertrain Warranty, the manufacturer is refusing to perform the required diagnostic tests (GDS Fuel Pressure Drop Test) to identify the leaking injectors. This failure to diagnose a known fuel system defect poses a significant safety risk to the driver and other motorists. The primary safety risk is unexpected engine stalling while the vehicle is in motion or stopped at intersections. Additionally, the loss of power during acceleration prevents the vehicle from safely merging into high-speed traffic, significantly increasing the likelihood of a collision. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Feb 26, 2026 · Transmission · TX

I was about to turn into a 2 lane road and a warning came on my dash, "shifter system malfunction service immediately " my vehicle was in Drive I was unable to move my vehicle, unable to shift into any other gear. It was sudden with no warning or loss of power prior to the warning and loss of movement.

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 Aug 3, 2023 · Acceleration, Electrical · WA

Hyundai filed Recall Campaign 236 for the vehicle entering an unsafe state. On July 10th I took in our 2021 Santa Fe Limited with just over 15,000 miles, which had been operating normally with the serious safety defect and received the Remediation for this recall filed under the federal safety agency Recall Campaign 236. I took possession back of the vehicle and within a few miles of driving had the exact issues the recall remediation was supposed to fix, occur. I lost the ability to safely control the vehicle followed by multiple warning lights displaying and then experienced full loss of power. I could not signal or use emergency blinkers while going at speed on I-405 between mile marker 5 and mile marker 6, this placed everyone around me on the highway at risk. I am deeply concerned that the Recall Remediation for Campaign 236 may not work.

Filed Feb 28, 2023 · Engine, Transmission · OR

When driving on the highway the suv would not change gears. It felt like it was stuck in 1st gear, reving very high. Was unable to move the suv to the side of the road. Came to a stop with heavy traffic blowing there horns. Put the suv into park, switched it over to sport mode and was able to get going. This is the third time the suv has lost power. Also have noticed the transmission has been taking to long to change gears.

Filed Dec 12, 2022 · Driver assistance, Electrical · CT

I was accelerating after being at a stop sign onto a major two lane road when all of the warning systems came on and the car stalled while the front of the car was partially on the major two lane road. The alarms, including the collision warning were going off, and it took me several minutes to restart the engine. I was very lucky that I was not hit by oncoming traffic. This was immediately reported to our local Hyundai dealer. They took two weeks to schedule our appointment and then told us nothing was wrong and that everything "checks out". Today, I receive the recall notice telling me the loss of power "could increase the risk of a crash" and yet they do not yet have a fix for it. This means I am paying for a car that is unsafe to use with no remedy in sight. Had this occurred on the highway, I would have been killed.

Filed Dec 10, 2022 · Transmission · IN

The issue first came up in June 2022. When driving the vehicle and coming to a stop the vehicle lost power and would not drive at all. After a few seconds the check engine light came on. After multiple attempts to shift into gear and restart the vehicle the vehicle did have power but for only about 10 miles before doing it again. We ended up having the vehicle towed to the Hyundai dealership. They told us it was a transmission electric oil pump going out (which is now recalled). They replaced the pump but immediately after getting the vehicle and driving down the road less than a couple of miles, the vehicle lost power again and did the exact same thing. The dealership towed the vehicle back and this time said they will need to replace the whole transmission assembly. After waiting over 3 months they finally replaced it. We got the vehicle back and currently is able to drive. However, the transmission shifts hard and there have been times where the transmission lags for a long time before shifting into gear to make the vehicle move. When it does finally go into gear the vehicle will take off real hard and quick. I do not feel safe in this vehicle. Considering how the vehicle lags and takes off real hard at times, I feel this is putting me at risk for a wreck. This is absolutely unacceptable for a vehicle this new and so few miles. Unfortunately, I do not feel Hyundai will back up their poor product and give a fair refund. We have received a recall notice for the oil pump but they have no solution. This recall does not take into account how poorly the transmission now shifts after being replaced.

Filed Dec 7, 2022 · Engine, Fuel system · WA

There were two warning (?) "bings" from the instrument cluster and then vehicle completely lost power and would not exceed maybe 2 MPH. Vehicle had forward drive, but no willingness for engine to speed up beyond idle speed. Was like this for several city blocks until I was able to restart at a traffic light and then it resumed normal operation. Did not notice any warning lights and no messages popped up in the instrument or vehicle display. Just the two "bings" before power loss. This is actually the second time this has happened. Last time was while accelerating on a freeway onramp, but vehicle corrected itself more quickly and without need for restart.

Filed Aug 19, 2022 · NY

While on a high speed highway in New Jersey the transmission suddenly lost power and the car was unable to move. It had to finally be towed to the Hyundai dealer on 7/26/2022 where it remains awaiting a new transmission. Neither dealer or Hyundai Corporate has any information as to when new transmission will arrive and be installed.