2017 Hyundai Santa Fe

We have been involved with an Oil Consumption problem since 2025 maybe earlier. No leaks just an over use of oil. I have had to fill it myself or take it to the dealer. They did testing and di some kind of cleaning that took 8 hours. We still have the problem and while driving the whole car shut down. No power in the middle of a highway. This has now happened twice and the first time we had to call AAA for help. It showed an engine sign and we checked the code. First it was an small air leak but they didn't find anything. It came up again, same message so we replaced the gas cap, but the oil was still disappearing and the car had shut down again. I spoke with the Hyundai corporation and they said to do the combustion cleaning again. So we set it up but found out that we had to pay for it so we declined. They refused to do anything about the car. We later found there were other cars made by the same company with the same problem. I did some research and they have had an Oil Consumption problem for quite a while. Now the Catalytic Converter is showing up as having problems. Well that's where the oil goes and can shut down the car due to airflow. They never disclosed it to us face to face, we had to find out about it after the the warranty was up. That was very dangerous to have stopped on a highway.

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.

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.

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)

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.

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.

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.

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.

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.