2017 Hyundai Santa Fe Engine Problems

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 9C2 campaign software update introduced dangerous vehicle hesitation and unpredictable gear changes in active traffic, presenting and immediate crash hazard

NHTSA ID

11753154

Incident

May 20, 2026

On June 10, 2024 at 107,129 miles Hertrich Hyundai dealership of New Castle inspected my vehicle and submitted a request to Hyundai for engine replacement under the recall settlement of the Theta II Engine Settlement. Hyundai denied the request because of the rebuilt title, even though the rebuilt title resulted only from prior Roof damage unrelated to the engine, powertrain, or recall issue. After continuing to seek assistance from Hyundai, my engine ultimately seized and suddenly stopped working on May 10, 2026, while driving on the highway with my two children. The vehicle lost power and stopped in traffic, creating a dangerous situation and causing my children extreme fear and distress. Had Hyundai honored the Theta II Engine Settlement when I first requested assistance, this failure could have been prevented. I request that Hyundai honor the Theta II Engine Settlement and replace my defective engine at no cost to avoid any future problems. My Hyundai Santa Fe is covered under the Theta II Engine Settlement. For over three years, I repeatedly contacted Hyundai after experiencing symptoms consistent with the known Theta II engine defect. Hyundai failed to provide meaningful assistance, did not properly process my requests, and denied coverage solely because of the vehicle’s rebuilt title.

NHTSA ID

11753050

Incident

Jun 25, 2026

I own a 2017 Hyundai Santa Fe Sport 2.4L (VIN: [XXX]). On XXX, my vehicle received Campaign 9C2 (ECU software update for Theta II emissions improvement). Shortly after this update, I began experiencing a drivability issue that did not exist beforehand. Description of the issue: The problem occurs only after the vehicle has been sitting long enough for the engine to become completely cold, typically overnight. During approximately the first 1/4 mile of driving, the vehicle intermittently jumps, surges, or lurches while accelerating normally. Once the engine warms up, the symptom completely disappears and the vehicle drives normally for the remainder of the trip. There are no warning lights, no check engine light, and no diagnostic messages. The Hyundai dealer has had the vehicle for nearly a week but has been unable to reproduce the concern. Because the issue only occurs during the initial cold start and first portion of the drive, I am concerned that it may not have been tested under the same conditions in which I consistently experience the problem. I am not claiming that Campaign 9C2 caused the issue, but the timing is notable because the symptom began only after the ECU update was performed. I am requesting Hyundai's assistance in determining whether: - the ECU update was installed correctly, - any required adaptation or relearn procedure is incomplete, - there are any related Technical Service Bulletins or software updates, or - additional diagnostics should be performed during a true cold-start drive with live data recording. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11751838

Incident

Jun 11, 2026

On July 4, 2026, I was driving 2.5 hours from home. My car stopped after about an hour of travel. The car shook and the check engine light came on as the car shut down. There were no warning lights on in my vehicle. I have oil change records. My car had burned through all the oil in an hour. This is not a new problem with this model Hyundai. Every group I went to discuss the problem online all had customers who reported their vehicles suddenly started burning oil quickly which resulted in damaged motor with no warning lights in the dashboard. I had to have my car towed from out of town to the dealership. The dealership that said I had extended warranty on parts of the motor. However upon checking the motor, they said it wasn't covered. I filled out a claims report with Hyundai motors who looked into the problem and also said it's not covered under warranty. This is a known issue of Hyundai with a failure to warn of low oil in the car's warning center. This is a fault of Hyundai. I've taken good care of my car and just paid $1000 for new tires on July 2, 2026 before my trip. The dealership quoted me a price of $3500 to replace the motor with a used one. It would also require 16 hours of labor which I Believe is $200 an hour. I believe they should replace the motor due to faulty systems. My car has 107,000 miles on it, but whenever I've gone to have it checked out, everything checked out fine even at the dealership. Also, this is a known issue that Hyundai is refusing to address with their customers.

NHTSA ID

11751827

Incident

Jul 4, 2026

After having the Service Campaign 9C2 ECU SOFTWARE UPDATE FOR THETA II EMISSIONS IMPROVEMENT, TSB 26-01-013H-2 done, my vehicle started having driveablity issues. On a normal, cold start the engine's RPMs go up really high, so I take my foot of the gas and the revs drop, almost stalling the car, and then the car bucks. I put my foot back on the gas pedal, and the engine revs really high again and takes off. If I try to drive normally, the car bucks and runs rough. My car also revs a lot higher during highway driving, than it did before the update. All of this is also causing terrible gas mileage. My car did nothing like this until I had the 9C2 update.

NHTSA ID

11750493

Incident

Jun 17, 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

The contact owns a 2017 Hyundai Santa Fe. The contact stated that after an unknown Emission recall was performed on the vehicle, the vehicle started sputtering at start-up and then while driving. There was no warning light illuminated. The dealer was notified of the failure and informed the contact that it was a known failure after the Emission recall repair. The contact was informed that the manufacturer was working on a fix for the issue. Additionally, the contact was advised that the recall repair was optional, but the contact had opted to have the vehicle repaired under the recall. The manufacturer was contacted several times, but no assistance was provided. The failure mileage was approximately 78,000.

NHTSA ID

11747342

Incident

Jun 9, 2026

Mileage

78,000 mi

vehicle serviced on 5/7/2026 for Hyundai service campaign 9C2 immediately after noticed car was not driving as it had been prior to this update, sluggish acceleration on start, chugging and then rapid sudden acceleration. returned to service dept May19. Diagnostics revealed no issues, problem persisted. returned to service dept. May22. Informed Hyundai was looking into this issue related to the 9C2 update and awaiting a new update to fix the problem. As of todayJune15 there has been no action to remedy the problem. Do not feel safe driving a vehicle that hesitates when starting to drive and then accelerates roughly. this has happened consistently upon cold start up thus far but concerned it may happen while in traffic or at other times and result in an accident.

NHTSA ID

11744314

Incident

May 7, 2026

See attached document for complaint.

NHTSA ID

11743251

Incident

Apr 14, 2026

My wife was driving our 2017 Hyundai Santa Fe around March 8, 2023 with our 3 children in the vehicle. She began merging onto interstate 70 when the vehicle made a noise and became undriveable. She could still steer but pushing the pedal down did not do anything. She had to carefully pull over off of the highway so that she did not get in an accident. This vehicle had to be towed to a mechanic who said the engine had seized up and that the oil is gone from the engine and that I would need to have it sent to a Hyundai dealer. This vehicle had 108,334 miles on it so it was just past Hyundai's 100,000 mile warranty. This vehicle was towed to a Hyundai dealer who confirmed that the engine was locked up and that an oil sample found metal in the oil. The dealership recommended to replace the engine with a used one for over $11,000 which I declined then charged me $160 for evaluating. No warning lights or indicators were ever showing any issues. We did notice sometimes after an oil change that they would state on the invoice that the oil was a half quart low. This vehicle was parked in a garage and never had a drop of oil leak. Hyundai recently extended the warranty for this vehicle to 150,000 miles and then declined my repair claim due to the repair not being done at a dealership. The sudden loss of power while driving was a scary incident for my family but thankfully no one was hurt.

NHTSA ID

11743206

Incident

Mar 8, 2023

The engine burns oil fast. You have to replace oil on a regular bases. The car also looses fluids fast as well. This causing the engine to over heat. This causes the cylinder to head blow.

NHTSA ID

11743064

Incident

May 8, 2026

I was told my top side of my engine failed, and they only cover bottom side engine failure. As well as pieces was missing. When I looked at the video it showed that my screws has fell off vs removed.

NHTSA ID

11742869

Incident

May 13, 2026

Air compressor and compression failed engine diagnostic test. Vehicle had high oil and gas consumption.

NHTSA ID

11742268

Incident

Jun 2, 2026

Hi, my name is [XXX], i bought used Hyndai Santafe sport 2017 from dealership in 2020. It had around 47,000 Miles on it, intitially it was running fine but after driving 2 years i discovered that engine is burning oil and after the oil change right after 1000 miles i had to add a quart of oil and it was like every two weeks. I had many srevices from dealership and other auto mechanic stores but it didn't improved. I had no choice but to keep driving the card on XXX th the engine crashed with out any sign on dashboard. There was slight noise and it increase by the way car was parked on the side road from Highway. The car was towed to my local mechanic and confirmed that engine is crashed. After i had to towed to dealership and i am still waiting for their response. Now we have put 43,000 miles in 6 years (91,000) total mileage. I had bought the waranty from dealership by $ 2500 which expired in 2025 Currently no warranty. My question here is that the car is still under 100,000 and engine failed. What if the dealership refuse to replace the engine. What are my leagal rights. Thanks [XXX] [XXX] [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11742118

Incident

May 26, 2026

reporting a serious safety concern involving my 2017 Hyundai Santa Fe Sport with the Theta II engine. While driving on the highway, my vehicle suddenly lost power without warning. The vehicle became unsafe to drive and I had to pull over and have it towed. There was no warning light before the failure. The vehicle has been regularly maintained. Hyundai later stated there was internal engine damage. My vehicle also shows an open engine-related recall/campaign since November 2025. I have found many similar complaints from other Hyundai owners describing sudden loss of power, excessive oil consumption, and engine problems involving the Theta II engine. I contacted Hyundai Motor America and provided documentation and videos, but I have not received a meaningful response. I am concerned this issue may represent a serious safety defect because the sudden loss of power occurred while driving on a highway.

NHTSA ID

11740312

Incident

Mar 28, 2026

The engine in my 2017 Hyundai Santa Fe Sport equipped with the 2.4L Theta II GDI engine is experiencing severe excessive oil consumption. The vehicle consumes approximately 2–2.5 quarts of oil every 1,000 miles despite multiple repair attempts and dealership-performed combustion cleaning procedures. Hyundai Motor America and the dealership documented the condition under PA #[XXX] and recommended engine replacement. Hyundai Motor America advised me in writing that the vehicle should not be operated in its current condition because of the excessive oil consumption and pending engine replacement. Excessive oil consumption creates a risk of sudden engine failure, engine seizure, stalling while driving, and potential engine fire if oil levels drop unexpectedly. Because the engine rapidly loses oil between normal service intervals, the vehicle may become unsafe to operate without warning, placing myself, passengers, and other motorists at risk. The defect was confirmed multiple times by Capital Hyundai in San Jose, CA through two official Hyundai oil consumption tests. The dealership documented oil consumption of approximately 2–2.5 quarts per 1,000 miles and submitted the results to Hyundai Motor America under PA #[XXX].The dealership also performed multiple repair attempts, including spark plug replacement, fuel induction cleaning, combustion chamber cleaning, and repeated oil changes, but the excessive oil consumption continued. Prior symptoms included: Check engine light illumination, Cylinder #4 misfire condition, Engine noise, Excessive oil loss between oil changes, and Oil level dropping significantly within short mileage intervals. The check engine light and misfire condition first became severe enough to require dealership diagnosis on or around [XXX], when the vehicle was towed to the dealership. The excessive oil consumption issue was formally documented beginning [XXX] during Hyundai’s oil consumption testing process. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6

NHTSA ID

11739834

Incident

Jul 15, 2025

I am submitting a complaint regarding a turbocharger failure on my 2017 Hyundai Santa Fe VIN [XXX] . The vehicle experienced turbocharger-related failure symptoms including loss of power and drivability concerns. This created a potentially dangerous situation because the vehicle was unable to accelerate normally and could have caused difficulty merging into traffic or maintaining safe roadway speeds. I contacted Hyundai Motor America requesting assistance with repair coverage. Hyundai denied assistance solely because the vehicle was outside the warranty period by time and mileage, despite the seriousness of the failure. I am concerned this issue may be related to broader engine or oil-related defects reported in Hyundai vehicles, including possible oil starvation, excessive oil consumption, or internal engine contamination that could contribute to turbocharger damage or failure. I believe this condition may represent a safety-related defect because sudden power loss during operation increases the risk of a crash. I request that NHTSA review this issue and investigate whether similar turbocharger or related engine failures are occurring in 2017 Hyundai Santa Fe vehicles. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11738896

Incident

Apr 15, 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

The contact owns a 2017 Hyundai Santa Fe. The contact stated that the vehicle was using an excessive amount of oil. There were no warning lights illuminated. There was no indication of a leak. The local dealer was contacted, but the vehicle was not diagnosed or repaired. The dealer informed the contact the failure was related to combustion chamber cleaning. The manufacturer was contacted, who informed the diagnostic fees were at her expense and there was no coverage. The failure mileage was approximately 94,700.

NHTSA ID

11736987

Incident

Mar 1, 2026

Mileage

94,700 mi

Engine seized up on the interstate. Vehicle has ~97,000 miles. Towed to dealership. Dealership wanted $8,000+ to replace engine. Hyundai refused to honor their warranty of 15 years/150,000 miles. Remains at the dealership, unrepaired.

NHTSA ID

11735603

Incident

Mar 31, 2026

My vehicle had oil consumption problems that were fixed with a new replacement engine now my catalytic converter is going bad due to engine oil consumption problems and the dealer I deal with is refusing to help with this issue. There is only around 50k miles on the new engine. I would greatly appreciate your help with this Thank you!

NHTSA ID

11735297

Incident

Mar 18, 2026

On 4/17/26 McDonalds Hyundai of [XXX] , dealership performed an ECU update for THETA II Emissions logic improvement (Hyundai campaign number 9C2). Ever since that time the vehicle has been lurching during acceleration. This happens particularly when the vehicle has been sitting for several hours. I reported this to the dealership on 4/28/26 (Scott, service manager) and to Hyundai on 4/29/26 (Hyundai Case Management #: 42610495). I noted to Hyundai that this same/similar problem has been reported by other owners ( see [XXX] ) INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID

11735182

Incident

Apr 17, 2026

The contact owns a 2017 Hyundai Santa. The contact stated that while driving at approximately 55 MPH, the vehicle stalled and hesitated to accelerate while the accelerator pedal was depressed. The check engine and check engine oil warning lights illuminated. The vehicle was taken to a local O'Reilly's, where it was diagnosed with ignition coil #3 misfire. The vehicle was not repaired. The vehicle was towed to an independent mechanic, where it was diagnosed and determined that the engine needed to be replaced due to severe engine oil consumption. The vehicle was then to a local dealer, where it was diagnosed with abnormal engine oil consumption, and the dealer determined that the engine needed to be replaced. The vehicle was not repaired. The contact stated that the vehicle required an engine oil refill 800-1,000 miles before an engine oil change was due. The contact related the failure to several unknown Hyundai TSBs. The manufacturer was made aware of the failure, and a case was filed. The failure mileage was approximately 87,000.

NHTSA ID

11735133

Incident

Mar 8, 2026

Mileage

87,000 mi