This vehicle and model have a defective engine; I have made several attempts since I purchased this vehicle from the dealership to have this issue corrected, and nothing has been done. This is a very common issue with this particular engine, and it is a well-known problem; there are several class action suits regarding this engine, and the manufacturers still have no resolution for it. The vehicle requires constant new oil in between oil changes and has been like that since new. The engine burns oil, and it is not going anywhere, nooen seems to know.

- Round Rock , TX, USA

We purchased a 2016 Hyundai Sonata in December 2020 for our son who is in college. In early August of 2022, my son noticed his oil light was coming on before it was time for an oil change. He had the vehicle topped off and maintained regular oil change and service schedule. While in for service at Fitzgerald Hyundai in Rockville, MD, August 2022, they replaced the spark plugs (4 cylinder tune-up) at 108,127 miles. The car continued to burn a lot of oil, so another appointment was scheduled at the dealership in Rockville September, 2022 at 111,792 miles. An oil and filter change, complete 23 pt. Vehicle Maintenance Inspection was performed, and all fluids topped off. The vehicle continued to burn oil at an unacceptable rate well before an oil change was required. My son continued to get oil changes and top off before the standard mileage. Another appointment was scheduled with the same dealer in Rockville, MD December 2022 at 118,989 miles requesting a diagnosis for the excessive oil consumption. After inspection, we were told an oil consumption test needed to be performed in order to determine why we are having this issue. We were also told that the spark plugs needed replacing again, less than 5 months from the previous replacement. Our service advisor said oil was probably shooting out onto the plugs. Hyundai denied the request to pay for the oil consumption test. The service advisor said she sees this a lot when I asked about excessive oil consumption on a vehicle with less than 120,000 miles. Also, they kept the car for almost 2 weeks.We are looking to rid ourselves of this piece of junk and purchase a vehicle by a reputable manufacturer. In the meantime, we are topping off and getting frequent oil changes. There definitely appears to be a defect with this year and model vehicle and Hyundai should acknowledge there is an issue and resolve it. I will never purchase another Hyundai and will spread the word to everyone I know, not to buy a Hyundai.

- Silver Spring, MD, USA

Huge amounts of oil consumption, have to refill all oil every 20-30 days. Car shut down on highway and went into limp mode, had to impede traffic to attempt to pull over safely. Potential known issue with Theta II engine, but dealership is declining a fix.

- Silver Springs, NV, USA

The contact owns a 2016 Hyundai Sonata. The contact stated that while driving at 45 MPH, she smelled a strong burning odor. The engine oil warning light illuminated. The vehicle was taken to the dealer who diagnosed that there was an oil leak. The dealer replaced the engine oil; however, the failure reoccurred while driving. The vehicle was taken back to the dealer twice, but the dealer diagnosed that no issues were found. The dealer replaced the engine oil again; however, the failure persisted. The contact stated that upon servicing the vehicle, the independent mechanic confirmed that there was an oil leak. The dealer was notified of the failure and advised the contact to take the vehicle in for a diagnosis. The manufacturer was not notified of the failure. The vehicle was not repaired. The approximate failure mileage was 45,000.

- Rockford, IL, USA