Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2017 Hyundai Sonata Hybrid owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2017 Hyundai Sonata Hybrid. The contact stated while driving 35 MPH, a message indicating a vehicle failure was displayed and the coolant temperature warning light illuminated. The contact stated that as she was veering to the side of the road, she saw white smoke rising up in the rear of the vehicle through the rearview mirror. Another driver also notified the contact of the white smoke. The contact stated that she parked the vehicle and opened the hood but could not determine the cause of the failure. The contact remained on the side of the road where she was waiting for the vehicle to be towed. The dealer and the manufacturer were not notified of the failure. The vehicle was not diagnosed or repaired. The failure mileage was approximately 116,495.
The contact owns a 2017 Hyundai Sonata Hybrid. The contact stated that on three separate occasions, the vehicle stalled. The contact stated that while his wife was driving at an undisclosed speed, the vehicle stalled. Several unknown warning lights illuminated. The contact's wife was unable to restart the vehicle. The contact stated that he was then notified by his wife of the failure and arrived at the scene to move the vehicle off the roadway. The vehicle was then towed to the dealer where it was diagnosed that the assembly generator failed and needed to be repaired. The vehicle was repaired; however, the failure recurred. The contact stated that while driving at an undisclosed speed, the vehicle stalled with several unknown warning lights illuminated. The vehicle was towed back to the dealer where it was diagnosed that the knock sensor failed and needed to be replaced. …
The contact owns a 2017 Hyundai Sonata Hybrid. The contact stated that while his wife was driving approximately 60 MPH, the vehicle lost motive power. The contact stated that the check engine warning light was illuminated. The contact stated that his wife was able to drive the vehicle to an independent mechanic. The contact stated that the mechanic retrieved various codes from the engine, and P1326 for the engine knock code and informed his wife that the engine needed to be replaced. The contact had the vehicle towed to a dealer who diagnosed the vehicle and performed a bearing clearance test and replaced the knock sensor. The dealer determined that the engine did not need to be replaced. The vehicle was repaired. The contact researched online and related the failure to NHTSA Campaign Number: 21V727000 (Engine). The manufacturer was informed of the failure. …
The contact owns a 2017 Hyundai Sonata Hybrid. The contact stated that after the vehicle was taken to a local dealer for an unknown recall repair, there were abnormal knocking, clicking, and flapping noises heard intermittently coming from the engine compartment. The contact also stated that the vehicle had reduced power steering assist and was stalling while driving uphill. The check engine warning light and other unknown warning lights were illuminated. The vehicle was taken to a local dealer on three different occasions; however, the mechanics were unable to duplicate the failure. The contact stated that the wiper blades and key fob were replaced. The vehicle was not repaired. The manufacturer was made aware of the failure and a case was opened. The approximate failure mileage was 15,000.
The contact owns a 2017 Hyundai Sonata Hybrid. The contact stated while driving at an undisclosed speed, the check hybrid system warning light illuminated. In addition, the vehicle lost motive power. The vehicle was serviced by a dealer two months ago and repaired under Technical Service Bulletin: T6G. The contact stated that the failure reoccurred after driving the vehicle for 500 miles. The vehicle was taken to the dealer where it was diagnosed with a failed engine and the contact was informed that the engine needed to be replaced. The vehicle was not repaired. The manufacturer was not made aware of the failure. The failure mileage was approximately 138,300. The contact called the case manager at Hyundai and he refused to give any confirmation about the problem with the engine.
The contact owns a 2017 Hyundai Sonata Hybrid. The contact stated that while driving approximately 60 - 65 MPH, the red engine warning light illuminated. The vehicle was towed to the local dealer who informed her the vehicle was working as designed. While driving on another occasion, the check engine warning light and the Hybrid System Shutdown and Turn Off Engine message was displayed. The vehicle was towed to the same local dealer where it was diagnosed and determined that the computer chip was faulty. The vehicle was repaired. The contact stated that on another occasion the check engine warning light illuminated again. The vehicle was towed to the local dealer but was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was approximately 80,000.
The contact's son owns a 2017 Hyundai Sonata Hybrid. The contact stated that while her son was driving at an undisclosed speed, he smelled a burning odor on the interior of the vehicle, after which he heard an abnormal sound coming from the engine compartment. The check engine warning light was illuminated. The vehicle was taken to the dealer to be diagnosed; however, the contact was not aware of the diagnostic report. The vehicle was not repaired. After investigating the failure, the contact related the failure to NHTSA Campaign Number: 21V727000 (Engine); the VIN was included, and parts were available. The contact also stated that the vehicle had a Salvage Title. The manufacturer was not notified of the failure. The failure mileage was 66,000.
The contact owns a 2017 Hyundai Sonata Hybrid. The contact stated while her husband was driving 65 MPH, the vehicle began to shake and lost motive power. The contact stated that her husband pulled off the highway safely. The driver then attempted to re-enter the highway, there was a loud bang from the engine that shook the vehicle. The vehicle stalled. The contact stated no warning light was illuminated. The vehicle was towed to a dealer and diagnosed. The dealer service manager informed the contact that the failure was related to NHTSA Campaign Number: 21V727000 (Engine) for which the VIN was included. The vehicle was not repaired. The manufacturer had not been informed of the failure. The failure mileage was approximately 75,000.
The contact owns a 2017 Hyundai Sonata Hybrid. The contact stated that while driving approximately 70 MPH with the accelerator pedal depressed, the vehicle started to lose power with the Hybrid and check engine warning lights illuminated. The contact veered to the side of the roadway. The contact shut off and restarted the vehicle however, the vehicle stalled and was not able to be restarted. The vehicle was towed to a dealer where it was diagnosed that the engine needed to be replaced under TSB: 209. The vehicle was repaired, but the failure recurred. The manufacturer was notified of the failure. The failure mileage was approximately 80,000.
The contact owns a 2017 Hyundai Sonata Hybrid. The contact stated while driving at various speeds, the contact noticed an abnormal ticking sound coming from the engine. There was no warning light illuminated. The vehicle was taken to the dealer, where it was diagnosed with engine failure due to the rod bearings failure. The dealer determined that the engine needed to be replaced and informed the contact that the repair was not covered under an unknown recall due to the mileage. The vehicle was not repaired. The manufacturer was not notified of the failure. The failure mileage was approximately 183,000.
Related recalls
Engine
Hyundai Motor America (Hyundai) is recalling certain 2017 Tucson and Sonata Hybrid vehicles. The connecting rod bearings inside the engine may wear prematurely, which can result in engine damage.
Remedy: Dealers will inspect the engine. If bearing damage is found, the engine will be replaced. Dealers will also install a software update containing a new Knock Sensor Detection System (KSDS).
NHTSA investigations
Engine Fires
On March 29, 2019, the Office of Defects Investigation (ODI) opened two Preliminary Evaluations (PE19-003 on Hyundai and PE19-004 on Kia) to broadly investigate incidents of non-crash fires (regardless of origin or operational status of the vehicle) on various model year Hyundai and Kia vehicles.
Loss of Motive Power
The National Highway Traffic Safety Administration (NHTSA) received a letter dated July 13, 2022, petitioning the Agency to initiate a safety defect investigation into loss of motive power allegations attributed to oil drain pan assembly failures on certain Hyundai Motor America, Inc. and Kia America, Inc. vehicles spanning Model Years (MY) 2005-2021.
Engine complaints in other Sonata Hybrid years
Frequently asked questions
How common are engine problems on the 2017 Hyundai Sonata Hybrid?
NHTSA has 50 complaints about the engine & cooling of the 2017 Hyundai Sonata Hybrid, 62% of the model year's 81 complaints.
Is there a recall for 2017 Hyundai Sonata Hybrid engine problems?
Yes — NHTSA recall 21V-727 (engine, Sep 17, 2021). Recall repairs are free at authorized dealers.
At what mileage do 2017 Hyundai Sonata Hybrid engine problems start?
Half of the complaints with a recorded mileage happened before about 80,000 miles, and 25% before 25,000 miles.
Is it dangerous?
Owners linked 1 crash, 2 fires and 0 injuries to engine & cooling problems on this model year. If you notice symptoms, have the car checked before driving further.
Source: U.S. National Highway Traffic Safety Administration (NHTSA) — owner complaints through October 20, 2026, recalls and defect investigations; fuel economy from the EPA. Complaints are unverified reports and are not proof of a defect. How we rate model years.