2017 Hyundai Santa Fe Sport: sudden loss of power

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 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 Jun 22, 2026 · SC

What component or system failed or malfunctioned, and is it available for inspection upon request? Multiple systems have failed sequentially — engine (replaced at ~84,000 miles), catalytic converter (replaced post engine replacement), and transmission (currently stalling, pending replacement authorization from Hyundai Corporate). The vehicle is available for inspection upon request. How was your safety or the safety of others put at risk? The vehicle stalls during the first few miles of every drive before stabilizing. This creates an immediate risk of accident on public roads, particularly at intersections, highway on-ramps, and in traffic. Despite this known safety hazard, the dealership returned the vehicle to me unrepaired on June 22, 2026, and deemed it safe to drive. Has the problem been reproduced or confirmed by a dealer or independent service center? Yes. Fort Mill Hyundai (805 Gold Hill Road, Fort Mill, SC 29708) has confirmed they can physically feel the stalling issue but stated they do not have sufficient data to submit to Hyundai Corporate for transmission replacement authorization. An independent mechanic also previously confirmed the engine issue that the dealership initially dismissed. Has the vehicle or component been inspected by the manufacturer, police, insurance representatives or others? Yes. Fort Mill Hyundai, an authorized Hyundai dealership, has inspected the vehicle multiple times over several years. The dealership is actively coordinating with Hyundai Motor America Corporate regarding the transmission replacement. Invoice reference: [XXX], dated June 22, 2026. Were there any warning lamps, messages or other symptoms of the problem prior to the failure, and when did they first appear? Yes. Check engine and brake warning lights first appeared at approximately 64,000 miles. These lights recurred repeatedly every ~1,000 miles despite multiple dealership visits. Subsequent symptoms included engine hesitation and loss of power, fol INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INF

Filed May 12, 2026 · Engine · NY

I was driving on a main road at 55-60 mph with my daughter and grandchildren in the car and had a sudden loss of power. I was almost hit from behind. The check engine light started blinking. And the car went into limp mode. I had to limp it to the nearest place to safely get off the road so as not to put my family in any other danger.There is not enough shoulder on the road to pull over safely. It was very stressful. Was able to get it in someone's driveway and then eventually towed to Auburn,NY Hyundai/Chevrolet where it is currently. It would not turn over to start again. It does have battery power. I am waiting to hear from the service techs as to what they think is wrong. They advised me that there is a $199 per hour diagnostic fee. I also told them that we noticed metal flakes in the oil when we checked it. I feel I should mention that the vehicle went into limp mode a few weeks ago also and the dealership told me the knock sensor was bad. I had that replaced at that time.

Filed May 10, 2026 · Electrical, Engine · AS

THIS IS AN UPDATE TO EXISTING the federal safety agency ODI COMPLAINT #11735718 2017 Hyundai Santa Fe Sport, TXXI Theta II engine defect. UPDATE: On May 7, 2026, Hyundai Case Manager acknowledged in writing "Your case is important to us" and "2.4L THETA concerns" for Case #42623761. This is written admission the vehicle has the TXXI defect covered by warranty extension to 120,000 miles. I gave Hyundai 48 hours to provide written authorization for oil consumption test per their TSB 22-EM-003H. After 3 days they are silent. They refuse email communication despite documented language barrier. Current Vehicle Status: - Active DTC P0010 causing loss of power and stalling risk - Oil Consumption: 1 liter per 600km, which is 3x Hyundai failure threshold in TSB 22-EM-003H - 95,772 miles, under TXXI 120,000 mile warranty limit - U.S. Spec vehicle covered by TXXI Warranty Extension Hyundai is violating Magnuson-Moss Warranty Act by refusing to honor written warranty for known safety defect. The P0010 defect causes sudden loss of power while driving. Requesting immediate the federal safety agency intervention to compel Hyundai to perform warranty repair.

Filed May 5, 2026 · Engine, Transmission · NY

COMPONENT FAILED: Theta II 2.4L GDI engine connecting rod bearings. Vehicle has 95,000 miles. Engine available for inspection in [XXX] . SAFETY RISK: Engine knock + limp mode at 1500 RPM caused sudden loss of power on highway. Oil consumption 1L/700km risks catastrophic engine seizure while driving. CONFIRMED BY DEALER: Independent service center confirmed DTC P0010 from metal debris. Hyundai Motor America Case #42623761 confirmed recall coverage but refuses remedy. INSPECTION: Manufacturer aware via Case #42623761. Local Hyundai dealers non-responsive. No police/insurance inspection. WARNING SYMPTOMS: Engine knock started at ~94,000 miles. Check Engine Light with DTC P0010. Progressive oil consumption. Limp mode activated at 95,000 miles. HYUNDAI VIOLATION: Hyundai confirmed via email they refuse to honor Safety Recall 162 / Service Campaign 966 Lifetime Warranty for VIN [XXX] despite all symptoms matching recall description. Request the federal safety agency compel Hyundai to authorize Bearing Clearance Test and engine replacement. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

Filed Jan 5, 2026 · Engine, Fuel system · NC

Component: Engine (Theta II 2.4L GDI) / connecting rod bearing-related failure risk with abnormal internal oil loss. The vehicle is available for inspection upon request (engine, oil level condition, diagnostic history, and dealer records). Safety risk: While driving on the highway (approx. 70 mph), the vehicle displayed a low oil warning, and I experienced concern for potential engine seizure/stalling and sudden loss of power, which could cause a crash. I reduced speed and sought service. This condition presents an ongoing safety risk because sudden engine failure can occur without adequate warning. Dealer confirmation: The problem was confirmed by a Hyundai dealer. After a routine oil change, the low oil warning appeared within ~1,700 miles. A Hyundai service center inspected the vehicle and documented the engine was approximately 3 quarts low with no external leaks, indicating internal loss/engine deterioration rather than a leak. Hyundai then required additional steps (combustion chamber cleaning and monitored mileage), and the abnormal internal oil loss condition persisted. Manufacturer inspection: The vehicle has been inspected by Hyundai dealerships, and Hyundai performed campaign-related actions, including KSDS/ECM update (T3G) and later knock sensor replacement. No police or insurance inspection. No crash or injury occurred. Warning lamps/symptoms prior to failure: Prior symptoms included a Check Engine Lamp with DTC P1326 (KSDS-related) documented by Hyundai service in 2025, followed by continued abnormal internal engine condition. The low oil warning occurred while the vehicle was in motion (highway speed). The issue remains unresolved, and I do not feel the vehicle is safe to operate due to seizure/stall risk. Additional: I reported this as a safety defect because similar Theta II engine issues are widely reported and can result in stalling, seizure, or engine fire. Hyundai denied engine replacement assistance despite the documented condition.

Filed Nov 11, 2025 · Engine · NC

The vehicle’s engine is experiencing excessive internal oil consumption that poses a serious safety risk while driving. After a routine oil change performed by an authorized Hyundai dealer, the engine oil warning light illuminated within about 1,700 miles. Upon inspection by another Hyundai service center, technicians confirmed that the engine was burning oil abnormally and was three quarts low, with no external leaks. This issue was documented in the dealer’s repair order, which states “vehicle is burning excessive oil.” The problem has been reproduced and confirmed by a Hyundai dealer. The vehicle is equipped with the Theta II 2.4L GDI engine, which is already covered under Hyundai’s KSDS (Knock Sensor Detection System) extended engine warranty due to known internal mechanical defects such as bearing wear and oil consumption. Despite this, the manufacturer has declined to replace the engine. The excessive oil burning occurs rapidly and triggers the low-oil warning light while the vehicle is in motion, creating a risk of engine seizure and sudden loss of power that could lead to a crash. The defect remains unresolved. Warning lights for low oil level appeared multiple times beginning in 2025, shortly after the KSDS update and knock-sensor replacement.

Filed Oct 3, 2025 · Engine · TN

On [XXX, I was driving on the interstate when my engine seized and the car lost all power, leaving me stranded on the side of the road on a busy exit at night. This was very dangerous to myself and others. I purchased this car in July of 2023 with 69,000 miles in good condition. I immediately made an appointment to take care of the recalls and updates to this car, which were performed February 2024 due to this being the first available appointment. Also, at my first oil change (3,000 miles after the previous oil change) I was told by the mechanic that there was absolutely no oil in my car. Since then I have had to put SEVERAL quarts of oil in between each oil change, costing me hundreds of dollars. Then June of 2024, the P1326 code flashed on my car and it went into limp mode also while I was driving on a busy street, putting myself and others in danger. I took it to the dealership and was advised to continue driving it and there was nothing they can do until my engine fails. I also brought up the oil consumption issue and was told that even if I did an oil consumption test (at my cost), there was nothing they could do. I was advised by my service advisor not to do a consumption test. I took his advice and continued to drive my car, adding countless quarts of oil weekly to my car. Fast forward to September 2024, when my engine light came on due to misfires in cylinder 3&4 and I took it to a local mechanic due to the incredibly long wait for an appointment at Hyundai. I was told all 4 spark plugs were oil fouled due to excessive oil consumption. This happened again July of 2025. My mechanic advised me that there was nothing to do about it, but that this would continue to happen due to the oil consumption issue. Now Hyundai is refusing to take responsibility for this engine that has had documented issues resulting in class action lawsuits and safety issues for myself and others and refusing any financial assistance. No warning lamps were on before incident. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATIO

Filed May 6, 2025 · Acceleration, Brakes · AL

While driving on a highway in April 2025, my 2017 Hyundai Santa Fe Sport suddenly lost all power after approximately 10 minutes of normal driving. All dashboard warning lights illuminated, and both the accelerator and brake pedals became unresponsive. I was forced to stop the vehicle using the handbrake in the middle of a 65 mph highway, creating an extremely dangerous situation for myself and other drivers. Prior to this incident, the vehicle had displayed the P1326 knock sensor code multiple times over a 10-month period, each time accompanied by hesitation when accelerating. The knock sensor was replaced twice under used car warranty by Honda. Despite these interventions, the same code and symptoms recurred. The Hyundai dealership(Dec 2024 at Montgomery, Jan 2025 at Enterprise) repeatedly stated that there was “nothing wrong with the engine.” After the highway failure, the vehicle was inspected by a collision center and an independent mechanic. They confirmed that Cylinder 4 had no compression and diagnosed a burnt valve. Full engine replacement was recommended. Hyundai initially indicated that the engine might be covered under the extended warranty but later denied the claim, stating that the damage was due to a cylinder issue and can not check bearing failure. They also claimed it was too late to determine whether the bearing was the cause. This is not an isolated issue. Many Hyundai owners across the U.S. have reported identical symptoms—P1326 code, hesitation, cylinder compression loss, and ultimately engine failure—particularly in vehicles equipped with the Theta II engine. These failures often occur around or after 100,000 miles, despite regular maintenance. This ongoing and widespread cylinder-related engine failure presents a serious safety risk and must be addressed through manufacturer accountability, improved diagnostic standards, and proactive repair or recall efforts.

Filed Dec 20, 2024 · Transmission · TX

The engine in my 2017 Hyundai Santa Fe Sport, specifically the 2.4L Theta II engine, failed and is available for inspection upon request. This failure caused the vehicle to stall unexpectedly while driving, creating a serious safety hazard due to the sudden loss of power and control. The issue has been diagnosed by a Hyundai dealership, which confirmed the engine requires replacement due to internal failure. The manufacturer has denied warranty coverage, alleging maintenance neglect by the previous owner. Prior to the failure, the Check Engine light illuminated, the vehicle began making knocking noises, and it experienced a loss of power before stalling.