2018 Hyundai Sonata fuel, hybrid & EV propulsion problems

Related recalls

No recalls on file.

What owners say

1. Filed Sep 4, 2026TXFuel, Hybrid & EV Propulsion

   My car stalls while driving and then I try to restart it but nothing happens. After reading online about the fuel pump issues and extended warranty related to the fuel pump I took the car in for repair. My car has 75,000 miles and the extended repair on this is for 150,000 miles/15 years. The dealer is refusing the repair because my car has a branded/ theft title. The car wasn't damaged just stolen. This is creating a serious safety concern and should be repaired by the…

   NHTSA complaint #11762281 · source
2. Filed Jul 24, 202692,000 miMSFuel, Hybrid & EV Propulsion

   The contact owns a 2018 Hyundai Sonata. The contact stated that while operating the vehicle, there was an abnormal fuel odor inside the vehicle. The vehicle was taken to the local dealer and was diagnosed with an inoperable low-pressure fuel pump. The contact was informed that the low-pressure fuel pump needed to be replaced. The vehicle was not yet repaired. The manufacturer was notified of the failure. The contact stated that the manufacturer had issued an extended…

   NHTSA complaint #11752670 · source
3. Filed May 12, 2026CAEngineFuel, Hybrid & EV PropulsionTransmission & Drivetrain

   Engine blown out malfunction took two dealer Hyundai Folsom Lake stated rings are bad sludge buildup in engine and stayed at Hyundai motor America denied engine replacement due to knowledge under Theta two engine extended warranty settlement of 150,000 MI 15 years I'm still within warranty but are still being denied had numerous of issues with vehicle oil consumption knock knock sensor replace and other maintenance done since purchase vehicle brand new in 2018

   NHTSA complaint #11737468 · source
4. Filed May 6, 2026TXEngineFuel, Hybrid & EV Propulsion

   I am submitting this complaint to report a serious and ongoing safety defect involving the engine of my 2018 Hyundai Sonata Sport equipped with the 2.4L Theta II engine. The vehicle has been officially tested and documented by Hyundai as consuming more than two (2) quarts of engine oil per 1,000 miles, which Hyundai has acknowledged following completion of its oil consumption test procedure. Despite this confirmation, Hyundai has declined to fully correct the defect. As the…

   NHTSA complaint #11736185 · source
5. Filed Apr 21, 2026WAFuel, Hybrid & EV Propulsion

   Throttle response intermittent problem no acceleration since new. No codes available. When entering traffic engine stall factor flat spot. Been to dealer many times (Bud Clary) and just recently (04/26) confirmed the fuel pump is the problem. Unable to confirm because of no "codes". Will not replace or register for recall without proper codes. No check engine lamp. No inspection by police or insurance only the dealership service department is aware of the problem.

   NHTSA complaint #11732817 · source
6. Filed Apr 2, 2026UTEngineFuel, Hybrid & EV Propulsion

   Had an oil change, then 2 weeks later car making noise, checked the oil and it was completely empty, so we refilled the oil. Then a month after again same issue no oil, refilled it again and now a week later it's 2 quarts low already. Also when I come to a complete stop when it is time to go again it's very slow at going or if I try to excel it takes it a very long time to actually excel I think something's wrong with the fuel pump

   NHTSA complaint #11728690 · source
7. Filed Mar 21, 2026AZEngineFuel, Hybrid & EV PropulsionTransmission & Drivetrain

   The vehicle developed a progressive engine failure beginning in early 2024, including loud knocking noises at cold start and visible white/gray/black exhaust smoke. The condition worsened over time. In February 2026, the failure escalated to active oil discharge from the exhaust pipe while the engine was running. Oil exiting through the exhaust indicates internal engine failure (such as piston rings, cylinder walls, or valve seal failure), not an external leak. This creates…

   NHTSA complaint #11726107 · source
8. Filed Mar 21, 2026ILEngineFuel, Hybrid & EV PropulsionTransmission & Drivetrain

   I bought a 2018 Hyundai Sonata a few years back. No warranty. Used. 110,000 miles. A few short months after I purchased it, it stopped working. I took it back to the same dealership where I purchased it and they said they had to replace the coil packs and spark plugs and clean something in the engine out because there's a defect in the engine. I paid $500. Fast forward a few months later. Same thing happens. I take it to an auto repair shop because it's cheaper and the…

   NHTSA complaint #11726097 · source
9. Filed Dec 16, 2025NJEngineFuel, Hybrid & EV PropulsionTransmission & Drivetrain

   While driving on the highway, my 2018 Hyundai Sonata experienced sudden loss of engine power and became undrivable. The failure occurred without warning at approximately 86,500 miles. At the time of the incident, there were two children in the vehicle, and the breakdown occurred at night in cold temperatures (approximately 20°F). An authorized Hyundai dealership later diagnosed zero compression in cylinder 3 and confirmed a cracked piston, recommending full engine…

   NHTSA complaint #11705457 · source
10. Filed Nov 22, 2025OHEngineFuel, Hybrid & EV Propulsion

    I am submitting a formal complaint regarding ongoing and severe engine issues with my 2018 Hyundai Sonata SE. Despite proper maintenance, the vehicle has developed extreme oil consumption and misfire problems that have made the car unreliable, unsafe, and financially burdensome. Beginning around 118,000 miles, the vehicle started consuming oil so rapidly that I was forced to completely replace the oil every 1–2 weeks because it would run dangerously low or nearly empty. This…

    NHTSA complaint #11700980 · source
11. Filed Nov 5, 2025GAElectrical SystemEngineFuel, Hybrid & EV Propulsion

    Unknown. 2018 Hyundai Sonata engine has failed. Only purchased the vehicle in December 2024, and the engine is defective. There is much information, via research, indicating that Hyundai is aware of the engine issues with this year vehicle, but are unwilling to make amends. Vehicle has 100,189 miles.

    NHTSA complaint #11697623 · source
12. Filed Sep 25, 2025ILElectrical SystemEngineFuel, Hybrid & EV Propulsion

    Oil consumption was ridiculously high, changing oil/topping off oil constantly. Car would not accelerate over 30 mph without sputtering and rumbling. I had mechanic diagnose bad sparks plugs due to sitting in oil from leaking. After I had them repaired/replaced the car drove great for 1 day, then decided to die in the middle of a busy intersection while I had my teenage son in the car with me. My son and I had to PUSH it out of the busy intersection onto a side street to get…

    NHTSA complaint #11689709 · source

Source: U.S. National Highway Traffic Safety Administration (NHTSA) Office of Defects Investigation public data. Complaints are submitted by owners and are not verified by NHTSA or by us; a complaint does not prove a defect exists. View this vehicle on NHTSA.gov Methodology