2017 Hyundai Santa Fe Sport vehicle speed control problems

“harsh engagement or hesitation between gears 1 through 3 specifically during cold starts before the powertrain warms up. But also during driving in the highway.”

“Campaign /Service Update 9C2 / TSB-25-01-087H broke my Hyundai. The car hesitates idling and on acceleration. Hyundai have no solution to this failed software update or acknowledging other issues it may be causing.”

“I took my SUV to get the 9C2 recall on 8/7/2026 performed and took it home. The next morning when I cranked it and left my driveway it acted as if the vehicle didn't recognize that I was pressing my accelerator. It sputtered and hesitated acceleration for about five minutes. It also acted as if it was not going to change from first to second gear. After about five min. of playing with the gas pedal it straightened out. Twice I was almost hit by other cars expecting me to pull away from a stop sign. I took it back the next day telling the service agent what was happening and he kept it overnight. I received a text saying the technician was unable to find a cold start problem and it was ready to pick up. I was so mad I could barely hold my temper. I took it home and for the next week every single day it acted like this when cold started in the morning. I took it back to Premiere Hyundai of Harvey and was treated rudely this time. They acted as if they never had a single other complaint and told me I might have to leave it for several days so they could cold start test it for several days. This was on a Wednesday morning 8/19. I was never updated or called and…”

“Brought my 2017 Hyundai Santa Fe Sport into the dealer on July 25, 2026 for the ECU and Theta II software update (Hyundai Service Campaign 9C2). Before the recall service my car drove perfectly with no issues. After the recall service my car is extremely jerky when shifting at low speeds and has long delays when trying to accelerate. This problem is particularly apparent on cold start, and less so once the vehicle has been driving. The issue is not as noticeable if the vehicle has been driven, is turned off, and then turned on again before fully cooled down. The jerky shifting has been getting worse over the past month. Vehicle was taken back to the dealer that conducted the software update on August 26, 2026 and they charged me for throttle body cleaning and EFI service which they performed for carbon build up as they cited this as the cause for the issues. The issue was not resolved from this service despite the dealers claims and the vehicle still has the same jerky shifting and delayed acceleration on cold start. There are no warning messages. Issue is becoming more widely documented among users after this particular service campaign so it is not an individual isolated problem.”

“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…”

“After the recent "important service campaign" involving the THETA II Emissions Logic Improvement my vehicle no longer safety shifts into the lower gears. It will not shift into gear. I am unable to safely get up to a normal speed and the engine and vehicle start shaking. This is isolated to the initial start of the vehicle and any low speed driving after. The issue is resolved after restarting the car, suggesting it is a software issue. This issue immediately began after the ECU update for the THETA II emissions logic improvement on 5/12/2026.”