really awful
Crashes / Fires:
2 / 0
Injuries / Deaths:
0 / 0
Average Mileage:
42,560 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 Subaru Legacy engine problems

engine problem

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2004 Subaru Legacy Owner Comments

problem #5

Feb 152006

Legacy 4-cyl

  • 20,000 miles


The contact owns a 2004 Subaru Legacy. The contact was driving approximately 30 mph when the vehicle decelerated independently. The check engine warning light was illuminated as the cruise control warning light began flashing. In addition, the vehicle would not accelerate over 10 mph. The vehicle was taken to the dealer for diagnostic testing where the technician advised that the throttle position sensor would have to be replaced. The vehicle was repaired however, the failure recurred six times. The throttle was replaced twice. The electronic control module was replaced and the manufacturer was made aware of the failure. The vehicle was not repaired. The approximate failure mileage was 20,000. The consumer stated the throttle ceased to function normally and the check engine light illuminated. The vehicle, would then slow down immediately and would only move at a speed of approximately 10 mph. The consumer stated he learned if he came to a full stop and restarted the vehicle three or four times, the throttle would re-engage and he would be able to resume normal speed, sometimes for some distance, and other times for only a short distance before it failed again. When the vehicle's electronic control module was checked by a mechanic, it showed a code P2138. It appeared that the engine computer unit was involved because when it rest the throttle worked again, briefly. The mechanic reset and it ran normally for three days before failing. Updated 05/16/13

- Charlestown, MA, USA

problem #4

Nov 092012

Legacy 4-cyl

  • 149,000 miles
Sudden deceleration. Occurred at complete standstill, 25mph and 65mph, speed appears not to be a factor. Check engine light comes on and cruise control quits and cruise light blinks and engine defaults to 1500rpm, all happens simultaneously, ergo no warning. Complete loss of gas pedal control. Intermittent problem. Can happen a few times a day or nothing for a week. Tends to happen more from a cold engine start and within 3 miles of thee start. Very dangerous if on freeway, especially in fast lane and pulling out onto street, etc.

- Springfield, MA, USA

problem #3

Apr 272010


  • 9,800 miles
The contact owns a 2004 Subaru Legacy. While driving at 2 mph, the vehicle suddenly accelerated and went through the garage wall. A police report was filed. The vehicle was towed to an authorized dealership but it had not been inspected or repaired at the time of the complaint. The current and failure mileages were approximately 9,800.

- Oceanside, NY, USA

problem #2

Jul 302009


  • 34,000 miles
I was steering the car, just leaving the lot of a home improvement store. I made a right turn, drove the distance of, perhaps, a city block and moved into the left lane to make a left turn. I had to stop for a red light so I applied the brakes but the car did not want to stop. The engine began revving! the gas pedal was stuck! feeling terrified, confused, not knowing what to do, I shoved the gear into park and turned the ignition switch to off. Later, I called the dealership and was given the "floor mat excuse" that the gas pedal had stuck for that reason; I was not told to bring it in for a checkup.

- Prospect, Ky, KY, USA

problem #1

Dec 172004

Legacy 4-cyl

  • Automatic transmission
  • miles
While applying the brake pedal vehicle accelerated uncontrollably. Driver continued to apply the brake pedal and the vehicle failed to stop completely. This caused the vehicle to collided into the vehicle in front. Vehicle was taken to the dealer for inspection, but mechanic could not duplicate the problem. However, the problem recurred. Second failure occurred while braking for a stop sign. The vehicle continued to accelerate an ran into the back of a pickup truck. There was no damage to pickup except that the vehicle's hood was caught in a trailer hitch on the pickup.

- Cohocton, NY, USA

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