Which parts fail
Components named in complaints (accelerator pedal, throttle, sudden acceleration, cruise control).
Mileage when the problem started
Owner reports
Selected complaints filed with NHTSA by 2004 Toyota Sienna owners, lightly cleaned up (personal details are redacted by NHTSA).
The contact owns a 2004 Toyota Sienna. The contact stated that while driving approximately 65 MPH the vehicle suddenly experienced unintended acceleration and the speed of the vehicle increased to over 90 MPH. During the failure, the braking system had failed and would not stop the vehicle while pressing the brake pedal. The front passenger was able to view the fuel pedal was stuck to the floor and was able to physically pull the fuel pedal up from the stuck position and the vehicle's speed was reduced. The incident lasted for approximately 10 minutes. During the incident, the police were on the scene. A police report was later filed at the scene and the vehicle was towed to the local dealer. The contact was informed by the dealer that the failure was due to a missing fuel pedal pen. No further information was available. The manufacturer was notified of the failure. …
Was driving on highway at 60-65 mph. The car continued to accelerate. Pressed on brake and wasn't slowing the vehicle. The driver was weaving in and out of cars as the van started to creek up to 92 mph. The driver and passengers thought they were going to crash and possible die. The driver tried the brake multiple times and nothing. The driver said the accelerator pedal wasn't pressed all the way down to the floor. It was half way and driver had to go down and pull up on the pedal while driving. The van then started to slow and driver was able to pull over to have the van evaluated . The throttle body was reached and cleaned of carbon because it said that this may have been part of the issue. Never has this van taken off like this. The throttle body cable wasnt loose or disconnected either. So far we havent been able to recreate but 3 people could have been killed.
- Traction control engaged at high speed(70 mph on interstate) causing the vehicle to brake abruptly and pull the vehicle to the right. Had I been traveling in the left hand lane, I could have been forced into the right hand lane causing a collusion with another vehicle. Also occurred at lower speed(30 mph on a windy road) causing the same issue as described above, almost causing the vehicle to leave the paved surface. - Mechanic was able to duplicate the issue - Mechanic diagnosed intermittent traction control activation, scanned computer for codes. Yaw rate/steering angle correlation causing false activation ABS/traction. Replaced hub bearing and spindle. Four wheel alignment, including check castor, camber and adjust toe. Performed zero point calibration and reset ABS memory. - Traction control lights up briefly
About a year ago the Vehicle Stability Control warning light along with an audible alarm started coming on intermittently while turning on highways going uphill or downhill in dry weather and with no risk of any tire slipping. At first this only happened at higher speeds 65+mph. Over time, it has occurred more and more frequently and can occur at speeds down to 25 mph. At times, the Anti-lock Braking System is also activated resulting in jerky braking and loss of throttle. When people have been following me too closely, this has almost caused accidents. When these symptoms occur, it is always on a curve (of any degree, even slight curves) and while driving at least 25 mph, and even happens on flat turns now. The weather has always been dry with no risk of tire slippage.
Vehicle often applies brakes on its own . At first it was only in turns . However now it does it when driving straight on the the freeway or just down the street at 45mph. I have fixed my alignment ,new tires, all of the front suspension and nothing prevents the car from trying to brake for me. it is a safety feature that is not safe at all. a car slamming on your brakes at any speed is dangerous in addition to that it seems to cut off your fuel , leaving you unable to accelerate until its done beeping which can take a long time. the vsc , chenk engine and trac off flash there is no crash to report I have been lucky so far
Sometimes when I take turns in my Sienna, the VSC starts going off and braking individual wheels without my control. This happens unexpectedly on highway bends at speeds of 60+ mph and it is difficult to control the car and keep from swerving into another lane. If the roads were icy when this happens, it would probably cause a dangerous accident. Toyota has a technical service bulletin for this, but not a recall - which it should since this is a significant safety issue. The TSB is BR008-04. There are many others experiencing this same issue: https://forums.edmunds.com/discussion/13855/toyota/sienna/vsc-sudden-activation-2004-toyota-sienna
I had the control arms replaced, then one of the bolts came out after a few thousand miles. I had that bolt replaced and the problem started happening intermittently after that. Everything will be functioning fine and then the speed of my vehicle is inhibited and it is hard to accelerate. It is very difficult to get from 40 MPH up to 50 MPH. On slight curves, not always, it will beep and the slip indicator light comes on and will apply the brakes on what feels like one side. This has happened at 35-60 MPH. The slip indicator will beep sometimes until I decrease my speed to under 25 MPH. I took it into a reputable tire and front end shop and they replaced a wheel bearing with sensor, and 2 front tires. The problem happened again within 5 miles and the shop said I need to take it to Toyota dealer to have it the steering angle sensors recalibrated. …
In May of 2008, I was attempting to pull my 2004 Toyota Sienna into the garage. I was idling when suddenly the vehicle took off. I was standing with both feet on the brake and could not stop. I crashed through the rear of the garage and hit a tree which ripped the right tire and axle from the drive shaft. At that point, I can to a stop however the engine continued to race until I turned off the vehicle. My 2 year old daughter had been right outside the back door of the garage when I crashed through. She was somehow pushed off to the side. The back portion of the wall and the back door went about 30 feet into the backyard. The tree I hit was about 45 feet behind the garage. I traveled for another 50 feet after hitting the tree and losing my right front tire. When we had the vehicle looked at by the Toyota dealership in sioux city, ia, they said nothing was wrong with the vehicle. …
Tl contact owns a 2004 Toyota Sienna. While driving less than 30 MPH in the right lane, the vehicle veered to the right. The vehicle almost crashed into the median. The contact steered to the left and the vehicle suddenly began to accelerate unexpectedly. He attempted to avoid oncoming traffic, but was unable to slow the vehicle down or come to a complete stop. The contact pulled into a parking lot and the vehicle crashed into a car wash. The crash occurred while the brake pedal was depressed. The vehicle is currently at a salvage yard provided by the insurance company. The driver sustained a fractured sternum and the front passenger needed 12 stitches in her right hand. The two rear passengers were uninjured. A police report was filed. The contact conducted online research, but found no recalls for the vehicle. …
I was driving in the middle lane on a three lane road. I arrived at a traffic light and came to a complete stop. I was standing in a traffic light with my foot on the brake. Standing in the same traffic light, there were many cars in front of my vehicle and several cars behind my vehicle. Suddenly, I felt my vehicle was attempting to move and smelled burning rubber from the right front tire. At the same time my foot was still applied firmly to the brakes and my vehicle jumped with a great force colliding with the vehicle in front me, which caused another impact and a third impact. The point of impact on my vehicle was the right side of the front of the vehicle. The left front tire was only two weeks oldand the other three tires were approximately 12,000 miles. The two front air bags deployed and the vehicle was totaled. …
Related recalls
Vehicle speed control › Accelerator pedal
Toyota is conducting a safety improvement campaign involving 26,501 early 2004 my sienna vehicles. In the event the retention clip used to secure the floor carpet cover is missing, the cover can interfere with the operation of the accelerator pedal if the acceleration pedal is depressed to nearly the full throttle position.
Remedy: Dealers will replace the retention clip and floor carpet cover at no charge. The campaign began on January 26, 2009. Owner notification is expected to be completed by early April 2009.
NHTSA investigations
Accelerator pedal interference
In a June 25, 2008, letter responding to an information request from odi, Toyota reported an April 2003 unwanted acceleration incident that occurred during production dynamometer testing.according to the letter the incident was caused by a missing retaining clip that allowed the center console trim panel to interfere with (trap) the accelerator pedal after it had been depressed.in the aftermath, Toyota reviewed…
Accelerator pedal interference
In a June 25, 2008, letter responding to an information request from odi, Toyota provided information about an accelerator pedal interference incident that occurred during production dynamometer testing at the assembly plant for an early production my 2004 sienna minivan.the incident was caused by a missing retaining clip that allowed the center console trim panel to interfere with (trap) the accelerator pedal after…
Acceleration complaints in other Sienna years
Frequently asked questions
How common are acceleration problems on the 2004 Toyota Sienna?
NHTSA has 111 complaints about the speed control & acceleration of the 2004 Toyota Sienna, 5% of the model year's 2,062 complaints. The component named most often is accelerator pedal (7 mentions).
Is there a recall for 2004 Toyota Sienna acceleration problems?
Yes — NHTSA recall 09V-023 (accelerator pedal, Jan 16, 2009). Recall repairs are free at authorized dealers.
At what mileage do 2004 Toyota Sienna acceleration problems start?
Half of the complaints with a recorded mileage happened before about 63,000 miles, and 25% before 25,000 miles.
Is it dangerous?
Owners linked 26 crashes, 0 fires and 11 injuries and 2 deaths 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.