Huge win for car owners! All TSBs to be made public. The Center for Auto Safety just made the NHTSA (US Government) make public the full text of all TSBs from now on. They are the same organization that has petitioned the NHTSA & filed lawsuits to protect car owners over exploding gas tanks & other major safety issues. Whenever you drive in your car, you are safer thanks in part to a lot of work over the years by this small but very effective consumer advocacy group.

Please take a moment & say thank you by donating $5 or whatever you can to the Center for Auto Safety.


really awful
Crashes / Fires:
2 / 0
Injuries / Deaths:
2 / 0
Average Mileage:
31,068 miles

About These NHTSA Complaints:

This data is from the NHTSA — the US gov't agency tasked with vehicle safety. Complaints are spread across multiple & redundant categories, & are not organized by problem.

So how do you find out what problems are occurring? For this NHTSA complaint data, the only way is to read through the comments below. Any duplicates or errors? It's not us.

2004 Hyundai Sonata engine problems

engine problem

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2004 Hyundai Sonata Owner Comments

problem #4

Mar 052013


  • 85,000 miles


Backing into the garage, my foot on brake, the engine suddenly revved to high RPM, the car shot backwards, propelling a heavy rubber mat on which the car is normally parked out of the garage and into the driveway. The vehicle then impacted and crashed through the rear garage wall before coming to a stop. I managed to pry the gear lever out of reverse, hit drive instead and sent the car, wheels still spinning and laying down rubber, forward out of the garage. On its way out the car swiped along the right side the garage door post before finally coming to a stop in the driveway. Final result, serious damage to both the car and the garage. Fortunately this did not occur in traffic or with pedestrians in the area. On-line research has since shown me that there have been numerous other similar incidents where Hyundai Sonatas have suddenly accelerated on their own. See

- Battle Creek, MI, USA

problem #3

Jan 312012


  • 30,000 miles
The contact owns a 2004 Hyundai Sonata. The contact stated that while driving approximately 5 mph, she applied the brakes and the vehicle suddenly accelerated forward. The vehicle continued to accelerate until crashing into the wall of a building. The airbags only deployed on the passenger side. The police were notified and a report was available. Both the driver and passeneger sustained minor bruising and were transported to the hospital via ambulance. The vehicle was towed to an independent mechanic and was pending an investigation. The manufacturer was notified via email and the contact had yet to receive a response. The failure and current mileages were approximately 30,000.

- Keizer, OR, USA

problem #2

Jul 212004


  • 9,000 miles
After starting the vehicle, it accelerated forward. The cause was not determined.

- Liverpool, NY, USA

problem #1

Aug 292004

Sonata 6-cyl

  • Automatic transmission
  • 272 miles
Vehicle stalled on two separate occasions while driving 45-50 mph. Vehicle was towed to the dealer, who replaced the throttle sensor the first time, but problem recurred. Vehicle was towed back to the dealer. Consumer had a concern of picking the vehicle up.

- Mount Laurel, NJ, USA

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