2006 Subaru Outback: adaptive cruise control problems

Filed Oct 14, 2021 · Electrical · ME

OBD Code P2138 (Throttle/ Pedal Position Sensor/ Switch D / E voltage correlation). This code pops up intermittently resulting in the car going into "limp mode". Truly dangerous, if this occurs when traveling at speed in traffic or when pulling away from a stop light. It is hard to pin down; but, it generally happens with high humidity or When you start the car after a cool night when there has been a lot of condensation that has formed on the car. A check of Subaru forums shows that this is a prevalent and / or recurring problem with many Subaru models. (I have also found mention of similar problems with other manufactures.) Dealers and mechanics have confirmed this problem with other Subaru makes. There is no advance warning of this malfunction until after it occurs. Once it occurs the car goes into "limp mode", the check engine light flashes and the cruise control light flashes.

Filed Sep 23, 2021 · Fuel system · 217,000 miles · CA

The contact owns a 2006 Subaru Outback. The contact stated while driving 55 MPH, the vehicle shut-off with the check engine and cruise control warning lights illuminated on the instrument panel. The vehicle went into limp mode as the contact steered the vehicle to the shoulder of the highway. Due to the failure, the contact had the vehicle towed to an independent mechanic where they diagnosed the vehicle with a defective throttle body. Neither the dealer nor the manufacturer was notified of the failure. The vehicle was repaired but remained in the possession of the dealer. The failure mileage was approximately 217,000.

Filed Mar 2, 2021 · Acceleration, Fuel system · 140,000 miles · UT

I experienced my gas pedal no longer working while driving, car was driving well, on a residential street going about 25 MPH, then there was suddenly no gas/acceleration, had to coast to a stop. The check engine light came on, cruise control light was flashing. About 2 hours later the car was running normal again. The diagnosis code given was p2138 throttle/pedal position sensor/switch d/e voltage correlation. It is very scary and unsafe to suddenly not have power while driving, will be driving on the outside lane until the problem is fixed to I can get out of traffic safely.

Filed Feb 19, 2021 · 156,000 miles · NC

I'm driving along & suddenly all the lights go on & the accelerator pedal does nothing, the car just loses power. I have to pull over, not always in a safe spot, because it won't do anything! Turn the car off & wait 5 minutes. Then it will start back up, with the check engine light & cruise control light blinking. After about 3 restarts those lights turn off. I've had theerror code read & its p2138. When a car just stops driving in the middle of traffic, it's very dangerous & I've been reading online that it's common in this year subaru & it needs to be addressed!! It's been happening more frequently & last time on the freeway!!!

Filed Feb 16, 2021 · Acceleration · 146,000 miles · AK

I was driving straight down the highway going about 50-60 MPH and out of nowhere my throttle peddle failed to work. My car immediately slowed down to a crawl and I had to quickly find a safe place to pull over on a road with barely any shoulder. Luckily not many cars were on the road so I did not have to worry about a pile-up accident. The check engine light came on and stayed on while the cruise control light began to flash on and off. After turning the car off and waiting a few minutes I decided to try and drive the car again since I was in an area with no service and it was below freezing outside. The car started and I could use the throttle peddle and the car drove with no problem for about 5 miles before the same exact thing happened. Luckily someone drove by and I was able to catch a ride with them to get service and call a tow truck. This issue came out of nowhere with no prior issues to the car. This is a very dangerous issue that could result in not only an accident on the road because of the rapid speed decrease but also risks leaving people stranded like I was.

Filed Nov 26, 2020 · Acceleration, Fuel system · 156,000 miles · CT

At highway speed the vehicle suddenly lost power. The check engine light came on solid with the cruise control light blinking. The car did not respond to any inputs from the accelerator pedal and began to decelerate. Upon stopping and shifting into neutral the car held itself around 2800rpm with no accelerator input from the driver. After reading the check engine light code, the car gave a p2138 indicating a problem with the pedal position sensor.

Filed Jan 17, 2020 · Electrical · 150,000 miles · WV

Vehicle developed issue error code p2138, throttle sensor on gas pedal desynchronizes causing vehicle to go into emergency safety mode where power is lost, goes into a high idle, and vehicle must be parked and restarted multiple times before powertrain reactivates. Caused by faulty design of potentiometer on throttle pedal that wears a bare spot. Replacement of throttle (gas pedal) required to resolve issue, which will eventually start occurring again due to poor design. Has occurred when pedal isn't being used (cruise control only), as well as during normal driving at all different speeds.

Filed Dec 3, 2018 · Acceleration · 170,000 miles · ID

Car will suddenly go limp. With no warning or anything the car is still running but there is no throttle or throttle pedal response. You can floor the gas pedal and nothing happens. It has happens while driving down a road and all you can do is hope that you can get to the side of the road. I was driving down a country road when this last happened. I came to a turn where you either have to stop or merge to the right onto another road. As I went to accererate there was no response from the car. I looked down and the check engine light is on as well as the cruise control light is now flashing. I tried turning the car off and back on several times. I finally shut the car off for 3-5 minutes before the throttle would respond. If this happened on the a busy freeway with heavy traffic, it could be very dangerous!!

Filed Nov 18, 2018 · Electrical, Transmission · 153,000 miles · MI

I was driving my 2006 subaru outback at around 40 MPH, going straight on a busy road. Without warning, the accelerator stopped functioning and the vehicle slowed down abruptly. It apparently entered a "safe" mode, with a maximum speed of about 10 MPH regardless of how much pressure I applied to the accelerator. The "check engine" warning light was illuminated, and the cruise control light began flashing. I pulled into a parking lot and turned off the ignition. When I re-started the car, the warning lights remained illuminated, but the accelerator functioned normally again and I was able to return home. The vehicle's engine management computer provided an error code p2138, throttle position sensor/switch voltage correlation. This appears to be a common problem with subaru vehicles from around this model year. It has the potential to be an extremely dangerous situation when the throttle suddenly stops working and the car slows to a crawl abruptly. My 17-year-old daughter is the main driver of this vehicle. If the error were to occur on the highway, it could cause a serious accident. There is no reason that the computer needs to put the vehicle in "safe" mode after sensing an electrical abnormality in the throttle wiring. I would like to request a recall to correct this extremely hazardous safety defect.

Filed Sep 10, 2018 · Acceleration · 183,000 miles · WA

While in motion, rapidly applying the brakes causes check engine light to come on, the cruise control indicator flashes and control of the accelerator pedal lost. The car essentially becomes limp and is not able to receive input from the accelerator pedal at this time. Turning the car off and letting it sit for 30 seconds and then turning the car back on re-provides control to the accelerator pedal. At this time the check engine light is still on. After a couple of days the check engine light goes off. My local authorized subaru shop traced the issue to a faulty accelerator pedal sensor. The entire assembly was replaced and the car is operating nominally. Two two instances where this caused a serious concern was when I was left stranded in the middle of an intersection when a car in front of me slammed on it's brakes and chose to turn right instead of the intended direction of travel straight through the intersection. The second time was to avoid an animal running across the road in front of the car. In both instances the car was moving at roughly 25mph.

Filed Apr 7, 2018 · Fuel system · 170,000 miles · MN

Today I came to a complete stop at a red light. When the light turned green and I accelerated, my vehicle began to sputter out. I tried to pull over but my car had no power. It began to sputter then died in the middle of the road. I was stranded at 9am on broadway with my 1.5 year old and 2 week old. I tried to start my car multiple times for 8 minutes until one attempt it turned over, this time with my check engine light and cruise control light flashing. It limped around for a while as I took it to a shop I was told the code read 'throttle positioning sensor'. Which I can't seem to find anything about let alone find it in a store or online. This experience has been frightening and dangerous and I have lost utter faith in my subaru.

Filed Feb 2, 2018 · Fuel system · 210,000 miles · IA

While driving my 2006 subaru outback down the highway, the accelerator became non-responsive. I was traveling at above 65 MPH and lost power. The service engine soon (ses) light came on and the cruise control light started flashing. I had to pull over to the side of the road. The car was still running at idle but nothing would happen when pushing the accelerator. I turned car off and waited for 15-20 minutes and restarted the car. The accelerator pedal then seemed to work as normal. My husband read the ses code (p2138 throttle position sensor). He checked the wiring connection at the foot pedal and it seemed fine. He reset the code with his code reader. The car drove fine with no issues for about 3-4 weeks but then had the same issue recur. This is a safety issue as I was very lucky I wasn't in the middle of a lot of traffic when this occurred. If I was I was pretty much a sitting duck as the car wouldn't move. I had to coast to the side of the road. There are quite of few other people on the internet that mention they have encountered this issue however most of them don't mention they reported the issue.