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 Subaru Outback owners, lightly cleaned up (personal details are redacted by NHTSA).
Tl* the contact owns a 2004 Subaru Outback. The contact stated that the accelerator pedal failed. While driving 35 MPH, the accelerator pedal stuck to the floorboard and caused the speed to increase to 70 MPH. The contact had to crash into a tree to stop the vehicle. The vehicle was towed to the contact's residence. There were no injuries and a police report was not filed. The manufacturer was not notified. The failure mileage was 230,000.
The automatic gear shift had been locked in park, which never happened previously. It eventually was released by putting the tip of a key into the area of the panel. Advised for this problem in the drivers manual. After driving the vehicle twice more , it was parked again. When the key was put in the ignition, there was a whirring sound and when it started, it surged forward very rapidly and could not be stopped by using the brakes.. The vehicle was out of control. It was off the road and rocks punctured a tire. It stopped. When brought to the Subaru repair shop, the insurance adjustor did not advise repair, because of heavy damage to the engine, transmission etc.
The car will be operating properly at speed on local roads (30mph or so) when, without warning, the engine will go to a fast idle and the gas peddle loses all effectiveness. Stopping the car and restarting it has fixed the problem the three times it has happened. The dealer replaced the accelerator pedal position switch but the problem has reoccurred. This is a potentially very dangerous situation, especially if it were to occur pulling onto a highway or being in traffic on a busy road
Tl contact owns a 2004 Subaru Outback. The contact stated while driving into a parking space the vehicle suddenly accelerated forward while the contact applied the brakes and crashed into a building. The contacts face hit the steering wheel and she also injured her ankle. The vehicle was currently in the dealers possession for diagnostic testing to determine what May have caused the sudden acceleration. The failure mileage was 67,000.
2004 Subaru Outback wagon, unwanted, uncontrollable acceleration, unable to stop vehicle resulting in collision, the collision incidents were while in reverse and the ambient temperature was cold ( 0-22 f). Generally the accelerator is oversensitive most of the time. Ira Subaru dealership has not been able to resolve problem. I had an independent repair shop look at it and they could not resolve it .
I was pulling into my driveway when I stepped on the brakes the car lunged forward and struck a boat on a trailer in my driveway sending it into the side of my home the more I stepped on the brake the faster the engine accelerated I eventually ended up crashing into a tree which finally stopped the car.
Unintended acceleration. Not driver error, not stuck floormat. Vehicle started accelerating above 7 on the tachometer. Pushed in clutch of course. Stopped with clutch in and vehicle just kept revving higher. Shut off car and restarted later. Terrifying.
My Subaru, forester xt has had numerous problems since it had 5000 miles. The engine performance is inconsistent. The car has an intermittent miss at idle, cruise control that disengages at will, is difficult to start intermittently; spitting and sputter for 30 seconds, acts as if it will stall occasionally while braking, and the clutch does not grip the flywheel properly. While passing on 2 lane roads, I have nearly had numerous head-on accidents; the car does not accelerate consistently. The cruise control defect has nearly caused many other accidents in distinct conditions: 1. While ascending hills, I have nearly been rear-ended by other cars when my car loses speed without warning 2. …
On two separate occasions, with two different drivers, my Subaru Outback 2004 vehicle experienced dangerous sudden acceleration. In both cases, we were stopped in traffic for a few minutes, foot on the brake, when suddenly, the car began to surge forward. Even exerting strong pressure on the brake, the car continued to surge forward, the engine racing. On one occasion, we were behind other stopped cars and almost rear-ended the car in front of us. On another, we were stopped at a cross walk and almost lurched forward into pedestrians. In both cases, we then threw the car into neutral (it is an automatic). The engine then raced wildly for a few seconds. We then threw it into park. At this point, the engine continued to race, then subsided. A moment later, the car was behaving normally again. Our initial calls to Subaru were regarded with lightheartedness. …
Tl* the contact owns a 2004 Subaru Outback. The contact stated that while driving approximately 65 MPH and the cruise control engaged, the vehicle erroneously accelerated. The contact also began to hear an abnormal sound in the front of the vehicle and deactivated the cruise control. The vehicle persisted to accelerate independently and the contact lost control of the vehicle. The vehicle was towed to an independent mechanic where it was diagnosed that the cruise control cable was disarranged causing the cruise control to fail. The vehicle was repaired however, the mechanic informed the contact that the vehicle was damaged due to a rod in the engine from the damage of the cruise control failure. The manufacturer was notified of the failure and informed the contact that the vehicle was not included in NHTSA campaign number: 04V128000(vehicle speed control). …
Related recalls
Vehicle speed control › Cables
On certain passenger sedans, wagons, and sport utility vehicles, the cruise control cable could come out of its track on the cruise control lever and lodge on the control lever tab when the accelerator pedal is released.
Remedy: Dealers will install a cruise control cable retaining clip to the cruise control lever tab on the throttle shaft in order to prevent the cruise control cable from coming out of its track.
Acceleration complaints in other Outback years
Frequently asked questions
How common are acceleration problems on the 2004 Subaru Outback?
NHTSA has 20 complaints about the speed control & acceleration of the 2004 Subaru Outback, 22% of the model year's 90 complaints. The component named most often is cables (1 mentions).
Is there a recall for 2004 Subaru Outback acceleration problems?
Yes — NHTSA recall 04V-128 (cables, Mar 16, 2004). Recall repairs are free at authorized dealers.
At what mileage do 2004 Subaru Outback acceleration problems start?
Half of the complaints with a recorded mileage happened before about 67,000 miles, and 38% before 25,000 miles.
Is it dangerous?
Owners linked 7 crashes, 0 fires and 2 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.