Hyundai Santa Fe Sport loss of power problems

Filed Oct 5, 2026 · Engine · WA

While driving over the pass the car suddenly lost power and was running very rough. Luckily there was an exit close by that we took and the engine died on the exit. We were able to get it started and get to a parking lot where it died and would not start again. While trying to start it in the parking lot the check engine light came on. So, after a $375 tow to the nearest town the mechanic discovered a damaged spark plug and the compression test showed 0 psi. The scope showed a hole in the piston. The car also leaks and burns oil. The mechanic recommended scrapping the vehicle since it would not be cost effective to repair it. The mechanic said ours is the 6th Santa Fe in their shop with a blown engine in the past month. It has not been inspected by anyone else.

Filed Sep 29, 2026 · Engine · IA

Service Campaigh 9C2 Following completion of Service Campaign 9C2 (Theta II Emissions Improvement), certain vehicles may exhibit a brief hesitation or rough shifting condition during cold start operation. My 2017 Hyundai Santa Fe sport has severe loss of power and rough jerky transmission after the update. This condition will definately cause unsafe driving and vehicle engine and transmission damage. Hyundai corporate and local dealerships indicate no remedy for this situation. Dealer also indicated that Hyundai corporate may not release a new software update to fix the issue. This is unacceptable.

Filed Sep 15, 2026 · Engine · NE

My 2018 Hyundai Santa Fe Sport (2.4L Theta II GDI, VIN [XXX], approx. 110,000 miles) has suffered a chain of engine and emissions-system failures that create a loss-of-power safety hazard. At about 80,000 miles, Hyundai replaced the original engine under warranty for excessive oil consumption, a defect Hyundai has acknowledged across the Theta II engine family. After only about 20,000 miles on that replacement engine, the catalytic converter failed and set a P0420 code. The vehicle now bogs down, hesitates, and loses power under acceleration. This is dangerous when merging or accelerating into traffic, where a sudden loss of power raises the risk of a collision. A restricted or failing catalytic converter causes exhaust backpressure and abrupt power loss, and the underlying oil consumption also risks low-oil engine damage and stalling. A catalytic converter should last far longer. This premature failure is consistent with the well-documented Theta II pattern in which engine oil consumption contaminates and destroys the converter substrate. It indicates the replacement engine Hyundai installed is itself consuming oil and damaging downstream exhaust and emissions components. I reported this to the dealer and to Hyundai. Hyundai declined to cover the catalytic converter, treating it as unrelated, even though its own warranty engine replacement is the direct cause. I am filing so this safety-related failure is documented. No crash, fire, or injury has occurred. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Aug 10, 2026 · Electrical, Engine · MN

In June 2026 I took my vehicle to Hyundai for a recall to the ECM module. After that my vehicle would lose power and hesitate to shift gears, and overall does not feel safe. Took vehicle back to dealer and they have told me that I have to wait for them to issue a recall fix for this now .

Filed Aug 2, 2026 · Acceleration, Fuel system · GA

On February 24, 2026, I had the 9C2 software update. My vehicle was being checked for oil consumption. Since then I have had issues with it hard shifting when first starting to drive and sometimes after I've been driving a while. This has continued miles down the road, sometimes over thirty minutes after driving. It also just feels continuously like it is not driving smooth. This only started after the update. I contacted HMA. The first person on my case (Gurvinder) told me I needed to return my car, not to drive it. I had bronchitis, so I did not immediately do that. The next person "Rainey" told me it is a KNOWN issue and they are telling people to warm their cars up for around 3 minutes, and it will be fine. I'd done that, and even driven longer than that. I told him that. I took my mother-in-law home from church miles from there after collecting her at the church door, etc... Getting to the hill at to her home, I didn't think it was going to get up it. Often I don't think I'm going to get out of my driveway, a dangerous driveway in a curve. He wanted Krause Hyundai to contact HMA Engineer. When I was at Krause, they didn't know how to get ahold of HMA Engineer. Dalton also said they can't back the update out. I'm on my third HMA Case Manager. She keeps changing what I've told her is wrong in the emails, I don't think she knows anything about cars. She won't listen when I say I spoke to Dalton at Krause; she keeps speaking to John. [XXX] said they can do diagnostic, but it will cost me. I refuse to pay as [XXX] and Gurvinder had months before wanted me to take it back to get fixed, and Rainey wanted Krause to contact the engineer. It is a known issue with a letter written by Hyundai. Getting a diagnostic code reading performed is not going to help. I'm afraid my vehicle will lose power on the road and I will be struck. I tried uploading both pdf and jpg, but it wouldn't let me. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jul 17, 2026 · Engine · TN

The Hyundai Theta engine is a bad design that has many recalls, a history of oil consumptions, and breakdowns that leave consumers in danger, on the roadside, and out of money. This engine has a design that causes worn engine components and high oil consumption causing reduced engine power, ruined spark plugs, and engine damage with no recourse as a owner. Recently, my family member had a hesitation that causes the car to run rough and display a check engine light. She was in traffic and the vehicle was stopping. Had this been on the interstate it could have been deadly. This IS NOT UNCOMMON for these vehicles. A quick Google search is nationwide proof of an issue with these vehicles and engines that the government needs to hold Hyundai accountable. This particular vehicle has been assessed by a Hyundai and confirmed it is consuming oil at a higher rate than normal, as many other owners have documented. With this most recent issue of stalling out, the mechanic indicated that excessive oil consumption entering the spark plug port has fouled the spark plugs as the design of the engine is flawed. The oil consumption was discovered at approximately 99,000 miles and several steps were completed to "fix" and confirm the issue. There is no "real fix" to the issue due to the inherent design of the motor. Again, this is not a new issue with these cars and there should be recourse that holds Hyundai accountable for bad and dangerous engines. The check engine light did come on as the vehicle began to stall and run rough in traffic.

Filed Jul 16, 2026 · Engine · 120,577 miles · MD

The contact owns a 2014 Hyundai Santa Fe Sport. The contact stated that while driving at undisclosed speeds, the vehicle started to lose power while depressing the accelerator pedal, with black smoke coming from the engine compartment. The oil, check engine, and battery warning lights were displayed on the instrument panel. The contact pulled over and discovered black smoke coming from under the hood. Due to the failure, the vehicle was towed to an independent mechanic, and the engine was replaced. Two weeks after the replacement, the starter failed to operate as needed, and the vehicle was towed back to the independent mechanic, where the starter was replaced. Upon investigation, the mechanic discovered the federal safety agency Campaign Number: 17V226000 (ENGINE AND ENGINE COOLING); and associated the vehicle with the recall. The contact was referred to the federal safety agency Hotline to report the failure. The vehicle remained with the independent mechanic and was not repaired. The manufacturer was not notified of the failure. The failure mileage was 120,577.

Filed Jul 13, 2026 · Engine · TX

Vehicle is a 2013 Hyundai Santa Fe Sport with the 2.4L Theta II GDI engine. A Hyundai dealer documented excessive oil consumption in December 2025 (3 quarts consumed over 1,703 miles during a dealer-administered oil consumption test; repair orders on file and available for inspection). On April 19, 2026, at 160,913 miles, following a highway drive, the engine developed a pronounced knock and vibration at low RPM and began stalling within seconds of idling in Park, with check engine and charging warning lamps illuminated. An engine that stalls at idle presents a safety hazard in traffic due to loss of power braking and steering assist. The vehicle was removed from service the same day, has not been driven since, and remains available for inspection. Knock Sensor Detection System software (Campaign 953) was installed and did not prevent the failure. Manufacturer has been notified in writing and consumer affairs cases are on file.

Filed Jul 1, 2026 · Engine · AL

The engine (2016 Hyundai Santa Fe 2.0L/2.4L Theta II GDI engine) suffered a catastrophic internal mechanical failure, specifically related to the known connecting rod bearing defect. The vehicle is currently un-driveable and is located at Serra Hyundai in Trussville, AL. The vehicle and its failed engine are available for inspection upon request. The engine suddenly failed and lost all power while driving at highway speeds in active traffic. I was forced to coast a dead vehicle across multiple lanes of traffic to the shoulder without any acceleration capability. Yes. The vehicle experienced a complete failure, cannot be restarted, and is currently parked at an authorized Hyundai dealership The vehicle is currently at an authorized Hyundai dealership awaiting a formal corporate inspection and evaluation for engine replacement approval. It has not been inspected by police or insurance. There were no long-term warning lamps, messages, or symptoms prior to the incident. The vehicle was operating normally until the exact moment of the failure, when the engine suddenly began knocking loudly, lost power, and stalled within seconds.

Filed Jun 29, 2026 · Engine · GA

Issue was first identified in September 2024 when a rattling noise prompted inspection, and the engine was found to be significantly low on oil. Excessive engine oil consumption was confirmed with failure during manufacturer testing. Vehicle emits occasional burning oil smell when idling after 10 miles+ driving. Vehicle failed a 1,000-mile oil consumption test following a “Dynamic Engine Clean” performed by a certified independent mechanic, with documented oil loss of approximately 2 quarts. Vehicle subsequently failed a dealer-administered oil consumption test, with documented oil loss of approximately 2.3 quarts within 1,000 miles. Engine oil levels have dropped to critically low levels between checks despite active monitoring and maintenance. This condition presents a risk of engine seizure, sudden loss of power while driving, and potential engine compartment fire due to oil consumption or leakage. The issue has been reproduced and documented by both an independent mechanic and a Hyundai dealership. Despite confirmed excessive oil consumption, the manufacturer has delayed corrective action and has required repeated oil consumption testing and engine cleaning procedures rather than proceeding with repair. This condition appears consistent with known defects associated with Hyundai Theta II engines.