2017 Hyundai Santa Fe Powertrain (other) Problems

Component/System Failed: Engine assembly (Theta II 2.4L GDI) and Exhaust/Catalytic Converter. Description: The vehicle suffered a failure associated with the known Theta II engine defects. Engine oil consumption and internal engine wear directly led to unburned fuel and debris entering the exhaust stream, resulting in severe catalytic converter restriction/failure. Safety Risk: The combined failure caused sudden loss of power while driving, engine stalling, and significant driveability hazards, creating an immediate risk of a rear-end collision on public roads. Confirmation & Inspection: The failure was confirmed and diagnosed by a certified service facility. Replaced components and diagnostic documentation remain available for inspection upon request.

NHTSA ID

11765645

Incident

Sep 2, 2026

Service update 9C2. Car hesitates or slightly bucks on a cold start. No remedy to fix yet.

NHTSA ID

11765542

Incident

May 6, 2026

Vehicle was brought to an authorized dealership for service, and while there Campaign 9C2 (ECU Software Update for Theta II Emissions Improvement) was performed. Immediately following this software update, the vehicle developed drivability degradation, specifically engine stutter/hesitation and rough transmission shifting during cold starts. When attempting to accelerate in the first few minutes of driving, the vehicle delays engagement and then suddenly surges or lurches forward unpredictably. This creates a safety hazard, as the unpredictable power delivery and lag prevent the vehicle from accelerating safely when merging into traffic or turning across oncoming lanes, placing occupants at an immediate risk of a collision. The software logic error is fully reproducible every time the vehicle has sat long enough to cool down. The dealership confirmed the update was applied. There were no warning lamps or symptoms prior to the 9C2 update; the failure was caused directly by the manufacturer's campaign software modification to the Engine Control Unit (ECU). The vehicle and its ECU are available for inspection upon request.

NHTSA ID

11763180

Incident

Aug 18, 2026

Cold-Start Hesitation & Rough Shifting: Following the 9C2 ECU update, my vehicle is experiencing a brief period of throttle hesitation, rough shifting, or jerky transmission behavior specifically during cold-start operations.

NHTSA ID

11760934

Incident

Aug 21, 2026

Known as an issue with Hyundai, but unresponsive to correct because no diagnostic code is sent. Transmission will shift extremely hard from 1st to 2nd gear randomly. In keeping track of the mileage, this appears to happen every 200 miles or so. Also, it faild to upshift correctly, making the entire car shudder. Also, at times it will not go into reverse gear. On one occasion, after finally doing so, it slammed so hard into reverse I almost collided with the car behind me.

NHTSA ID

11760479

Incident

Aug 27, 2026

My 2017 Hyundai Santa Fe, purchased new from Lynnes Hyundai in February 2017, has approximately 93,000 miles. The vehicle previously developed a significant oil-consumption/engine problem that was diagnosed by Hyundai, and Hyundai replaced the engine with a remanufactured engine. Approximately two weeks after the engine replacement, the check-engine light illuminated and DTC P1326 was identified. The dealership replaced the knock sensor. Approximately two weeks later, the check-engine light illuminated again with a recurring P1326 condition. The vehicle is currently at Lynnes Hyundai and has been there approximately three weeks while they attempt to determine the cause. Hyundai Techline is involved. Prior to the current repair visit, while traveling approximately 60 mph, the vehicle experienced a very forceful hesitation that jerked the vehicle. I immediately slowed down and pulled onto the shoulder. The vehicle continued to hesitate intermittently while I drove slowly to safety. I was concerned that the vehicle could lose power or shut down while I was driving at highway speed, creating a risk of a crash. The recurring P1326 condition has been confirmed by the Hyundai dealership. The vehicle and engine have been inspected by Hyundai/Lynnes Hyundai multiple times, including after the engine replacement. The current recurring condition has not been resolved. The check-engine light is the warning lamp associated with the current condition. I do not know the underlying cause of the recurring P1326 condition; Hyundai is currently attempting to diagnose it. The vehicle is currently available for inspection at Lynnes Hyundai.

NHTSA ID

11759120

Incident

Aug 11, 2026

Complete unmitigated loss of acceleration and power while traveling at highway speeds, creating an immediate life-threatening road hazard. Following a warranty engine replacement and mandatory dealer software flash at Clay Cooley Hyundai (Sherman, TX), the vehicle began experiencing powertrain communication issues. While operating the vehicle at 65 MPH on the highway, the vehicle completely failed to accelerate and lost propulsion power, nearly resulting in a catastrophic rear-end collision with an oncoming 18-wheeler semi-truck. Dealership diagnostics claim "no trouble codes present," but live data telemetry confirms the High-Pressure Fuel Pump (HPFP) is actively commanding and delivering a dangerous 1,600 PSI to the fuel rail at hot idle. This abnormal fuel delivery is paired with a severe powertrain stutter in 3rd gear. Service personnel at multiple locations confirm a widespread, high volume of transmission failures and severe drivability issues specifically tied to this recent Hyundai software update. Corporate has denied repair coverage. The vehicle remains an active highway safety hazard and is completely undrivable.

NHTSA ID

11756411

Incident

Jul 8, 2026

The contact owns a 2017 Hyundai Santa Fe. The contact stated that while reversing, the vehicle jerked and shuddered abnormally. Additionally, the transmission hesitated, and the vehicle almost stalled. No warning lights were illuminated. The vehicle was taken back to the dealer where the contact was informed that the Service Campaign Number: 9C2 was completed. The contact was informed that the updated software was confusing the transmission and had caused the failure. The contact was informed that the remedy was not yet determined. In addition, the contact was informed that the dealer was waiting on instructions from the manufacturer. The vehicle was not repaired. The manufacturer was made aware of the failure but provided no assistance. The failure mileage was approximately 63,036.

NHTSA ID

11755907

Incident

May 22, 2026

Mileage

63,036 mi

The 2017 Hyundai Santa Fe was brought to dealership on 3/27/26 for an oil change and a computer update was completed for Emissions Improvement. Upon picking the vehicle up after service, it was noticeable that it was not shifting correctly. I spoke to the service department and asked if the memory was cleared with the update an if it was having to relearn how I drive and the said it should not be affected. This went on for a few days and I left the car with them to duplicate as there were3 no stored codes. After a few weeks, the Teck Line recommended a new transmission, which Hyundai offered goodwill assistance. As we were waiting for the transmission to arrive from being on backorder, a bulletin for Service Campaign 9C2 was release on 5/18/26 that described my experience with shifting issue almost exactly. The transmission was replaced and the drivability issues still persist. Hyundai says that I must let my car warm up for 1-3 minutes to allow a catalyst to reach temperature and not cause rough shifting. This rough shifting is the effect of the update and thus te reason that my transmission needed to be replaced. Further investigation showed that this update is a known issue and cannot be reversed once installed. Currently, I must start my car in 90 degree weather to warm it up as a result of this update which is not logical in any thought process. I have asked Hyundai to cover the balance of the new transmission as this is a result of thier faulty software update with no success.

NHTSA ID

11755540

Incident

Mar 27, 2026

A Hyundai recall 9C2 update was applied to my vehicle. Ever since that update my vehicle hard shifts on cold starts which I fear is damaging the transmission. Hyundai dealer was able to replicate this and keeps advising us that concern is ‘under review with Hyundai’. I have the service order that states this. This problem has been ongoing for Months! I think Hyundai needs to find a resolution to this as my research indicates it is impacting a lot of customers.

NHTSA ID

11755044

Incident

Jun 24, 2026

My 2017 Hyundai Santa Fe (VIN: [XXX]) was brought to Herb Chambers Hyundai of [XXX], in December 2023 to address the Underbody Corrosion Recall/Campaign (9A0). The dealer performed the preventative service. However, the remedy completely failed because the frame was already severely structurally compromised by rust. In early 2024, I relocated to [XXX] with the vehicle. Now 2026, The front subframe sub-assembly deteriorated to a hazardous point, forcing me to spend a large sum of my own money on front-end repairs caused directly by this corrosion. Currently, the rear subframe and rear suspension components are heavily corroded and structurally disintegrated. The vehicle is completely unsafe to drive, presenting an imminent risk of structural collapse and suspension failure while in motion. Hyundai's recall remedy was ineffective and merely masked the rust. The rear subframe (crossmember/cradle) and control arm anchor points are severely corroded, rusted out, and crumbling to the touch, creating an imminent risk of suspension collapse while driving. The extreme corrosion has spread to the metal fuel line the vehicle is unsafe to drive due to the advanced corrosion . Denial of Service by Local Distributor: The vehicle is currently located in the U.S. territory of Puerto Rico. I presented the vehicle and documentation to the local authorized distributor, Sojitz de Puerto Rico (Hyundai of Puerto Rico). As indicated I brought the Vehicle to MVP Hyundai Humacao (XXX) and filed a claim (# XXX) However they never sent a anyone to inspect the vehicle or process a safety claim, claiming they bear no responsibility because the vehicle was imported from the mainland, Because this is a failed federal safety campaign remedy that now poses an immediate threat to my life and public safety, INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11750549

Incident

Jun 6, 2026

The vehicle is in limp mode and is displaying a flashing check engine light with a P1326 powertrain code. The vehicle in question is a 2017 Hyundai Santa Fe Sport equipped with a Theta II 2.4L GDI engine at 118,000 miles. Per the service campaign T3G, listed on the NHTSA website, this vehicle is covered under warranty repair since it is a Theta II engine vehicle that is displaying an active P1326 power train code. The vehicle is under he 10 Year/120,000 miles limitations of the extended warranty. The dealer just submitted to us a quote to repair the vehicle and is stating that none of the repairs listed are covered under warranty. This includes a quote to replace the engine knock sensor, which is a warranty item under the T3G service campaign’s extended warranty.

NHTSA ID

11749634

Incident

Jun 29, 2026

Hyundai Campaign 9C2 recall update: Took my vehicle in to have the Hyundai Campaign 9C2 recall update performed on the vehicle on June 9th, 2026. Since the update the vehicle is hesitant/jerky upon first drive of the day or anytime it sits more than a few hours. Occasionally it will do this while I am driving. I feel it is a saftey risk because this could cause my vehicle to abruptly hesitate without braking and cause someone to hit me, or worsetransmission to fail while at highway speeds. I took it back to the dealer that performed the required update around june 23rd 2026 and informed them of the problem caused by the 9C2 campaign update.I got the we don't know anything about it causing problems runaround. Even though it has been documented that dealers were notified of this problem. They then wanted to charge me a $100 diagnostic fee to see if it might be something else, I declined that because I know it is from this update. My vehicle ran perfectly fine and smooth before this update was applied and no CEL lights are on. I did this update because it was required to be done by Hyundai. When I started researching why my vehicle was hesitant/jerky after the update is when I found that anyone that did this update is having these same issues, and it has been happening for a while now and Hyundai corporation has done nothing to correct this problem other than tell us to sit for at least 3 minutes or more before driving it. That does not help when it does it even after driving for a bit and possibly creating transmission problems.

NHTSA ID

11748778

Incident

Jun 9, 2026

We are driving on the highway and the engine just stop working but all lights are still working. I am trying to put gas but it seemed that the engine completely shuts off dangerously without warning. This put my family at risk because there were a lot of big trucks beside us. Theta II 2.0L Turbo engine just stalled I believe this has been around . Can you please help us.

NHTSA ID

11747482

Incident

Jun 29, 2026

My vehicle experiences severe, unpredictable harsh downshifting/surging when slowing down, specially from 3rd to 2nd and 2nd to 1st gear. The transmission kick causes unexpected vehicle hesitation and deceleration changes in active traffic: presenting an immediate crash hazard. The dealership head technician has physically test-driven the vehicle and confirmed the failure. However, Hyundai Corporate is refusing to replace the failing transmission under 10 years/100,000 mile warranty because the vehicle's computer has not yet thrown an electronic error code. The manufacture is actively trying to force me to drive an unsafe vehicle until the transmission completely fails in traffic, putting my family and other drivers at severe risk. May 28, 2026 currently milage is around 88,000. The dealership currently has the vehicle.

NHTSA ID

11740634

Incident

Apr 6, 2026

After the installation of the Service Campaign 9C2 engine update, the car now seems to surge or rev up briefly at lower speeds like it can't find the right gear or is trying to briefly accelerate. It doesn't seem to be as noticeable at highway speeds, but in residential or low speeds, it's very noticeable and a little unsettling as the car feels like it wants to briefly lunge forward. No lights are on the dash and there is no indication of any malfunction, but it did not behave this way prior to the 9C2 engine program update. I waited for a couple weeks before contacting Hyundai Corporate about this issue because I was hoping maybe the transmission or engine was relearning after a battery disconnection, but it has not gone away.

NHTSA ID

11738814

Incident

May 4, 2026

On April 2, 2026, the engine in my 2017 Hyundai Santa Fe failed catastrophically while my wife was driving. The vehicle lost power suddenly and completely. There was no warning and no prior symptoms. She was able to pull over safely in a residential area. The vehicle was towed to an authorized Hyundai dealer, where the service representative suspects connecting rod bearing failure—the same failure mode described in NHTSA recalls 17V226 and 17V578 affecting other 2017 Santa Fe vehicles with the Theta II 2.4L engine. The engine is available for inspection upon request. My VIN does not appear in the recall population, yet the failure is identical to the documented defect. This suggests the recall scope was insufficient. One week prior, we drove this vehicle on a 500+ mile family road trip with our child. The failure that occurred could have happened at highway speed. We are lucky to be alive. No warning indicators appeared before the failure. The vehicle has been regularly maintained. The problem has been preliminarily confirmed by the dealer as suspected bearing failure, pending teardown.

NHTSA ID

11729427

Incident

Apr 2, 2026

I purchase the 2017 Santa Fe Sport in October of 2023 with just short of 80K miles. It was in great condition and had no issues. I have maintained it according to Hyundai specification and regular on schedule oil changes with recommended 5w-20 full synthetic. At approximately 100K miles, I experienced an oil pressure light on the dash, when checked, the engine was approximately 2 quarts low. From this point on, the engine started consuming oil at an increasing rate all while I maintained regular maintenance. First, 1 quart a month, or about 1200 to 1500 miles, then to 1 quart every 2 weeks or 800 miles. I maintained weekly checks on the oil level and on the evening of 3/24/2026, I had added a quart, bringing the level to the midway point between the high and low dipstick markings. On the afternoon of 3/24/26 while driving on the highway in heavy, but at speed limit, traffic on the highway, I experienced a loss of power and a check engine light. I was able to exit the highway but the car started to run very rough and unable to idle. Luckily, there was no traffic approaching when I turned off the exit and made a left into parking lot to shut off the vehicle. I will be having it towed to a dealership in the next few days for their analysis.

NHTSA ID

11727630

Incident

Mar 24, 2026

I have a 2017 Hyundai Santa Fe with ~88,000 miles. I noticed on 12/18/2025 that the oil lamp light came on briefly then turned off. So, I decided to take my car in to get serviced on 12/19/2025. I was told that there is an oil consumption issue with the engine and that Hyundai would need to do a combustion cleaning, and worst case scenario a full engine replacement. Hyundai refuses to cover us under warranty because we transferred the car from my Mother-in-Law's name to my wife's name. I want to file this as a complaint to the NHTSA because a car that isn't even 10-years old AND has less than 90,000 miles should not be needing an engine replacement. Hyundai appears to be aware of the issue as my service advisor at the dealership has mentioned that several of their cars with this engine have the exact same issue. To me, this sounds like a defect and should have a recall.

NHTSA ID

11708307

Incident

Dec 18, 2025

“My 2017 Hyundai Santa Fe Sport 2.4 has been experiencing severe oil consumption issues for a long time. I previously completed a combustion chamber cleaning service as recommended, but the problem continued. On November 10, the Hyundai dealership confirmed the engine oil was low and topped it off. On December 10, the oil was completely empty again with no warning lights. The dealer has documented the issue and recommended an engine replacement, but Hyundai is refusing to approve the repair . The vehicle continues to lose oil rapidly, creating a serious safety risk of engine failure or stalling while driving. This appears to be a known safety-related engine defect affecting this model.”

NHTSA ID

11704714

Incident

Jun 6, 2025

# **NHTSA Complaint Answers** ### **1. What component or system failed or malfunctioned, and is it available for inspection upon request?** The **engine** failed due to **sudden and extreme oil consumption** that resulted in the engine being completely dry of oil despite regular maintenance. This caused internal damage including **CVVT (Continuous Variable Valve Timing) system failure**, bearing damage, and a complete engine seizure. Yes, the failed engine is fully available for inspection upon request. The vehicle is currently located at Dick Smith Hyundai in Greenville, South Carolina, where the dealership diagnosed the failure and recommended a full engine long block replacement. ### **2. How was your safety or the safety of others put at risk?** The engine failure occurred **suddenly and without warning**, causing the vehicle to lose power while operating. The loss of engine function created the risk of: * sudden deceleration in traffic, * inability to accelerate or maneuver, * potential rear-end collision, * complete engine stall in unsafe conditions. The vehicle had **no oil warning light** prior to the failure, meaning I had no indication that the engine was at risk until the failure occurred. ### **3. Has the problem been reproduced or confirmed by a dealer or independent service center?** Yes. The engine failure was confirmed by: • **Schwab’s Automotive** in Fayetteville, NC – determined the engine suffered catastrophic internal damage and was not repairable. • **Dick Smith Hyundai** dealership – confirmed **high oil consumption and CVVT damage**, and recommended a full **engine long block replacement** (estimate: $8,160.60). The problem has been fully verified by both an independent mechanic and an authorized Hyundai dealership. ## **4.Yes.The vehicle was formally inspected by Hyundai Motor America through the dealership’s diagnostic report. Hyundai reviewed the case (Case #XXX) after receiving the dealership findings.The engine remains intact avai. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF IN

NHTSA ID

11704253

Incident

Oct 23, 2025

While driving on the highway at normal speed, the vehicle suddenly lost power with no prior warning lamps or messages, placing me and other road users at immediate risk. The engine rapidly began knocking, lost acceleration, then stalled completely. I had to coast to the shoulder, which was extremely dangerous in high-speed traffic. The failure appears consistent with bearing wear and debris circulation described in Hyundai Recall 168 and TSB 17-01-071, which warn that certain Hyundai 3.3L engines can suffer internal metallic debris contamination during manufacturing. This can restrict oil flow, damage the bearings, and lead to sudden engine seizure without warning — exactly what happened in this incident. After the failure, the engine was inspected by a Hyundai dealership, but no oil sample, no debris test, and no photo documentation were provided, even though the recall procedure requires these steps when symptoms match knock/no-start failure patterns. The cause was not reproduced or confirmed by any independent mechanical test; the vehicle simply failed suddenly and has remained inoperable since. The incident created a major safety risk because the sudden loss of power happened at highway speed with no safe way to maintain vehicle control or speed. Based on known recall documentation, the symptoms match the described safety-related engine defect. The vehicle remains available for inspection. There were no injuries or police reports, but the situation definitely could have resulted in a crash. In my assessment, this is a critical safety defect related to internal engine debris and bearing failure, consistent with the known Hyundai recall pattern for this engine family

NHTSA ID

11701758

Incident

Oct 25, 2025

This vehicle has experienced numerous serious failures, including two engine replacements, a transmission replacement, and persistent safety system malfunctions. The Downhill Brake Control (DBC) system remains stuck in the "on" position, and the traction control warning light stays illuminated. These issues directly compromise vehicle safety and stability, particularly on hilly or wet roads. Despite extensive service at Arapahoe Hyundai in Centennial, CO, these problems continue to return. The vehicle has been in the shop multiple times and was most recently in service for nearly 30 days. My wife was stranded at the dealership today due to the same unresolved safety system failure. Dealer communication has been poor, and repairs are often incomplete, requiring immediate return visits. The repeated failure of safety-critical systems, combined with the inability to resolve the issues long-term, presents a significant safety concern for both my family and others on the road. I am requesting NHTSA to investigate whether this is part of a broader defect pattern affecting 2017 Hyundai Santa Fe models and if a recall is warranted.

NHTSA ID

11678332

Incident

Jun 16, 2025

Was driving on [XXX] (approximately 130 miles from home), when a loud clunking and metal on metal sound was heard, the causing power loss, slowing of vehicle and necessitated immediate pulling over to the side of the road. The was a catastrophic internal engine failure which caused the spark plugs to blow out. There were no warnings. The car was just inspected and had an oil change earlier in the month. The vehicle suffered sudden power loss and violent metal-on-metal destruction while transporting my child on [XXX] (130 miles from home). Certified diagnostics from Kennett Square Quick Lane Auto confirm: "Multiple spark plugs forcibly ejected due to severe internal engine damage – full replacement required". Quick Lane said they would not be able to replace the Engine. so the Vehicle was towed to Reliable Car Connection (West Chester, PA). I had tried to make an appointment at Piazza Hyundai, but the did not have appointments until Mid August. Result: Stranded overnight requiring hotel and towing/tolls at personal expense (receipts available). This traumatic event directly stems from Hyundai’s acknowledged Theta II defects. Hyundai’s Documented Failures: Recall Compliance: Recall 996 (Piazza Hyundai, 4/12/24) Recall 953 (1/31/19) Recall 163 (7/18/17) Maintenance: All services performed per Hyundai schedules (records available). Unresolved Defects: This failure matches: Recall 20VH4 (Lifetime Warranty Extension) Recall 20VH5 TSB 20-01-033H Current Status: Vehicle at Reliable Car Connection (West Chester, PA) after Piazza Hyundai’s unacceptable 6-week delay. INOPERABLE & UNSAFE – Cannot transport children. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11674102

Incident

Jun 29, 2025

2017 Santa Fe, car had fire in 09/2024 and was with dealership until 05/2025. BSD, ABS, TRACTION, and Parking Brake lights on the dash when vehicle was picked up. Dealership not complaint to pay as the assume it is an Outside issue

NHTSA ID

11670835

Incident

Sep 25, 2024