Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2009 Hyundai Sonata owners, lightly cleaned up (personal details are redacted by NHTSA).
Tl* the contact owned a 2009 Hyundai Sonata. While driving approximately 10-15 MPH and making a left turn, the vehicle independently accelerated to approximately 50-60 MPH. The vehicle crashed into a telephone pole. The air bag deployed. The contact sustained two broken legs, a broken ankle, and several broken ribs, which required medical attention. A police report was filed. The contact was extracted from the vehicle using the jaws of life. The vehicle was destroyed and towed to an impound lot. The vehicle was not diagnosed. A dealer was not contacted. The manufacturer was notified and provided case number: 15535396. The approximate failure mileage was 81,000.
Tl* the contact owns a 2009 Hyundai Sonata. While reversing, the vehicle violently accelerated and struck a light pole. The contact shifted into drive and the vehicle accelerated again. The contact mentioned that the tires were spinning. After several attempts, the contact shifted into park and the vehicle stopped. The vehicle was restarted and drove normally. There were no injuries. The vehicle was not taken to the dealer for diagnostic testing. The manufacturer was notified of the failure and opened a case. The vehicle was not repaired. The approximate failure mileage was 180,000. The VIN was unknown.
Tl* the contact owns a 2009 Hyundai Sonata. The contact stated that while his son was attempting to park at the car wash, the vehicle inadvertently accelerated causing the vehicle to jump the parking barrier hitting the vacuum machine. No injuries were sustained however the vacuum machine was damaged along with the front bumper was cracked and scratched. The manufacturer was notified and the vehicle was inspected at rick case (180 satellite blvd duluth ga, 30096) where no failure was determined. The failure mileage was 142,000.
Tl* the contact owns a 2009 Hyundai Sonata. While parking, the vehicle accelerated in reverse. The contact attempted to apply the brakes, but the vehicle kept accelerating. The contact crashed into the vehicle in its rear. There were no injuries and a police report was filed. The vehicle was towed and was not diagnosed or repaired. The manufacturer was not notified of the failure. The failure mileage was 62,000. Ma 08/05/2015 updated 9/24/2015
On 10/08/2009 my 209 Hyundai Sonata went into an unintended acceleration. As soon as I put the car into drive it began to accelerate. The brakes did not work and I was able to shift into neutral. I was on a narrow dirt road with little limited options as to where to steer the vehicle. I missed a boulder, garage, and tree before hitting the side of a house. The ambulance was called and I was transported to the local emergency room. I had a concussion, fractured knee along with a number of bruises and abrasions. The emts told me how lucky if was since the air bags did not deploy.. An internet search, including your website, notes these problems going back several years. Toyota had the same problem and did a recall. My injuries will exceed the limit of my insurance and I will have to purchase a car. I know how lucky I was to walk away. …
Tl* the contact owns a 2009 Hyundai Sonata. The contact stated that as he started his vehicle with the brakes engaged, he shifted to reverse and the vehicle accelerated suddenly without warning. The contact crashed into a telephone pole. He then shifted into drive with the brakes still depressed when the vehicle rapidly accelerated again and crashed into a concrete wall. The contact sustained whiplash to the neck. The police were notified and a police report was filed. There were extensive damages to the rear and front bumper of the vehicle but the vehicle was not destroyed. The manufacturer was notified of the acceleration issue and a representative was sent to further inspect the failure. After the inspection, the representative advised that the vehicle was operating as normal and no failures were found. The failure mileage was 94,782.
Upon accelerating up an entrance ramp to the highway, car accelerated at an unreasonable rate of speed tried using brakes, but they were gone. Car hit speeds of 60/65 MPH for more than 3 miles on a turnpike. Parking brake did not work, brake pedal was down to the floor and I could not control the speed of the auto. After traveling more than 3 miles, in the shoulder, I put the gear into neutral and the car began to slow down and finally stop. Towed from turnpike to dealership. Know there have been problems with the 2006 model, but is there anything similar to my experience with the Sonata 2009.
Tl* the contact owns a 2009 Hyundai Sonata. The contact stated that the shifter became stuck in park. The contact was able to shift into drive however, the vehicle then abnormally accelerated and caused the contact to crash into a wall. The contact did not sustain any injuries. The contact took the vehicle to a dealer to have repairs under NHTSA campaign I.d. 13V113000 (exterior lighting, service brakes, hydraulic) however, the dealer stated that the recall defect could have caused the vehicle to accelerate. The failure mileage was 65,000.
I was at the gas pump trying to ease up to get closer so the nozzle could reach my tank. In the process of easing up the car took off forward, causing the door to close my leg in the door almost causing me to loose my leg. The accelerator got stuck.
Once the car gets slowed down and reaches 20 mph of speed by applying the brake or not. It gives a sudden jerk, which causes immediate reduction in speed.
NHTSA investigations
Throttle control system vulnerabilities
The Office of Defects Investigation (ODI) of the National Highway Traffic Safety Administration (NHTSA) received a petition letter dated October 10, 2021, requesting an investigation of possible defects in the electronic throttle control (ETC) system on certain Kia vehicles resulting in the opening of DP21-003.
Acceleration complaints in other Sonata years
Frequently asked questions
How common are acceleration problems on the 2009 Hyundai Sonata?
NHTSA has 31 complaints about the speed control & acceleration of the 2009 Hyundai Sonata, 7% of the model year's 460 complaints.
Is there a recall for 2009 Hyundai Sonata acceleration problems?
No. NHTSA lists no speed control & acceleration recall for the 2009 Hyundai Sonata, though it has 2 recalls for other components. If the problem is widespread, a repair may still be covered by an extended warranty or a manufacturer service bulletin — ask a dealer.
At what mileage do 2009 Hyundai Sonata acceleration problems start?
Half of the complaints with a recorded mileage happened before about 51,000 miles, and 28% before 25,000 miles.
Is it dangerous?
Owners linked 7 crashes, 1 fire and 6 injuries to speed control & acceleration 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.