Problems · by component
2009 Hyundai Sonata engine problems
56 owner complaints to NHTSA about the 2009 Hyundai Sonata cite engine, 12% of all 460 complaints for this model year.
Complaints
56
12% of all complaints
Crashes
2
Reported by owners
Fires
3
Reported by owners
Injuries
4
Reported by owners
What owners say about the engine
Verbatim from NHTSA complaints, newest first
“Engine leaking oil from the front cylinder bank’s valve cover or leaking from the valve cover’s gasket onto the alternator. A sufficient amount of oil could damage the alternator resulting in illumination of the charging system warning lamp and disablement of the charging system. If the vehicle is continually driven with a disabled charging system, the engine can shut off, increasing the risk of a crash.”
“Oil Leak on Alternator Engine leaking oil from the front cylinder bank’s valve cover or from the valve cover’s gasket onto the alternator. An unknown amount of oil damaged the alternator resulting in illumination of the charging system warning lamp and disablement of the charging system. If the vehicle is continually driven with a disabled charging system, the engine can shut off, increasing the risk of a crash.”
“5/18/24 in the afternoon, driving the car on freeway. the car lost power. AC stopped. Heat and check engine lights came on. Pulled car to shoulder. Driver’s window was foggy. Smoke coming from front. Exited the car. Flames seen underneath front of car and passenger compartment. Smoke worsened and within minutes 10 foot high flames engulfed the car. Fire department had to extinguish the flames. And California Highway Patrol blocked off several lanes. The vehicle totally was incinerated. I filed a police report number 240518LA2144. I do not have the report yet. It is not ready. It was filed with the California highway patrol.”
“Vehicle sat in driveway for one week while on cruise. The day of return the sonata caught on fire without any person touching the car for one week. Brother who’s house it was at was woken by neighbors at 7sm. Home had minor damage, but it could of been bad if it was in someone’s garage. Fire started in engine and console. Fire department could not find out a reason. Car was totaled. Had to rent a car to get home that was 2 hours away. Never had an issue with this vehicle in the 12 years I owned it.”
“Valve cover gasket leaks and oil leaks on to the alternator which can cause the alternator to fail and the battery to not maintain a charge and the car can stall and then not start. This is the same exact problem problem that is in your recall on 2007-2012 Veracruz Recall number 20V705000 & 14V415000 And 2007-2009 Santa Fe vehicles have the same issue and Service Campaign 936 SB-10058931-4495 (TSB# 15-01-031).”
“The contact owns a 2009 Hyundai Sonata. The contact stated while driving 50 MPH, the vehicle inadvertently lost motive power and stalled. There was no warning light illuminated. The vehicle failed to restart. The contact pushed the vehicle to the side of the road with the assistance of her father. The vehicle was towed to an independent mechanic who referred the contact to the local dealer. The vehicle was then towed to the local dealer where it was diagnosed that the fuel pump needed to be replaced. The fuel pump was replaced; however, the failure persisted. The dealer then diagnosed that the gasoline needed to be pumped out. The repair was completed; however, the failure recurred. The battery was replaced; however, the failure persisted. The dealer diagnosed that the engine needed to be replaced. The vehicle was not repaired. The contact stated that the vehicle had been at the dealer for 3 months. The manufacturer was notified of the failure and a case was opened. The failure mileage was approximately 140,000. The dealer stated the car needs a new engine.”
Showing 6 of 56 reports. Read every report on NHTSA.gov.
Data from NHTSA Complaints API (owner reports, unverified) · synced Nov 10, 2026NHTSA vehicle page
Complaints are unverified owner reports to NHTSA and are not normalized for sales volume. One complaint can cite several components.