2018 Hyundai Santa Fe Sport engine problems

“This vehicle has been suffering from substantial engine oil consumption, burning oil at an alarming and unsafe rate. I have repeatedly brought the vehicle to Washington Hyundai to address this under the engine class-action lawsuit terms, but the dealership continues to run repetitive tests without a resolution. This is a critical safety issue. Excessive oil consumption poses a severe risk of sudden, catastrophic engine seizure or stalling while operating at high speeds on the highway.”

“My 2018 Hyundai Santa Fe is burning oil and I run the risk of engine failure. I have to check my oil level daily. The mechanic who performed my last oil change said he is seeing this frequently with this age Hyundai Santa Fe. He said Hyundai should be willing to replace my engine but of course they won't. I fear that I am going to be on the freeway and have sudden engine failure creating a risk for me and drivers around me.”

“While driving over the pass the car suddenly lost power and was running very rough. Luckily there was an exit close by that we took and the engine died on the exit. We were able to get it started and get to a parking lot where it died and would not start again. While trying to start it in the parking lot the check engine light came on. So, after a $375 tow to the nearest town the mechanic discovered a damaged spark plug and the compression test showed 0 psi. The scope showed a hole in the piston. The car also leaks and burns oil. The mechanic recommended scrapping the vehicle since it would not be cost effective to repair it. The mechanic said ours is the 6th Santa Fe in their shop with a blown engine in the past month. It has not been inspected by anyone else.”

“My 2018 Hyundai Santa Fe Sport (2.4L Theta II GDI, VIN [XXX], approx. 110,000 miles) has suffered a chain of engine and emissions-system failures that create a loss-of-power safety hazard. At about 80,000 miles, Hyundai replaced the original engine under warranty for excessive oil consumption, a defect Hyundai has acknowledged across the Theta II engine family. After only about 20,000 miles on that replacement engine, the catalytic converter failed and set a P0420 code. The vehicle now bogs down, hesitates, and loses power under acceleration. This is dangerous when merging or accelerating into traffic, where a sudden loss of power raises the risk of a collision. A restricted or failing catalytic converter causes exhaust backpressure and abrupt power loss, and the underlying oil consumption also risks low-oil engine damage and stalling. A catalytic converter should last far longer. This premature failure is consistent with the well-documented Theta II pattern in which engine oil consumption contaminates and destroys the converter substrate. It indicates the replacement engine Hyundai installed is itself consuming oil and damaging downstream exhaust and emissions…”

“Bought this as a used vehicle with around 77k miles. The SUV was running fine for a little while until I drove onto the highway. It eventually began to bog down and there was hesitation and jumping instead of acceleration. This continued my entire trip home with the check engine light on. The car was only driven for about 300-400 miles in the time I had it. When I brought it to have an oil change, they found metal shavings in the oil. From what I’ve been reading, this has been a common problem for this vehicle. It has been sitting in a Hyundai service center for at least a month now with no real responses from Hyundai themselves. They told me they would not fix the problem due to lack of maintenance from prior owners and that they were marking my title (doesn’t make sense since I bought this with a clean title). According to what Hyundai told me, this issue was brought up by a previous owner in January 2026 with no repairs. How can you change the status of my title while refusing to repair a problem caused by a manufacturers defect?”

“The Hyundai Theta engine is a bad design that has many recalls, a history of oil consumptions, and breakdowns that leave consumers in danger, on the roadside, and out of money. This engine has a design that causes worn engine components and high oil consumption causing reduced engine power, ruined spark plugs, and engine damage with no recourse as a owner. Recently, my family member had a hesitation that causes the car to run rough and display a check engine light. She was in traffic and the vehicle was stopping. Had this been on the interstate it could have been deadly. This IS NOT UNCOMMON for these vehicles. A quick Google search is nationwide proof of an issue with these vehicles and engines that the government needs to hold Hyundai accountable. This particular vehicle has been assessed by a Hyundai and confirmed it is consuming oil at a higher rate than normal, as many other owners have documented. With this most recent issue of stalling out, the mechanic indicated that excessive oil consumption entering the spark plug port has fouled the spark plugs as the design of the engine is flawed. The oil consumption was discovered at approximately 99,000 miles and…”