🔧 FixIt
🟡

P2138 on SUBARU LEGACY

Severity
Medium
NHTSA Reports
17
Most Affected
2006, 2005

What P2138 Means on Your SUBARU LEGACY

Real SUBARU LEGACY Owner Reports (Source: NHTSA Complaints Database)

"Driving southbound on hwy 17 at 60mph 11/15/2020 engine suddenly went to idle. throttle became unresponsive. check engine light illuminated. i drifted to safety off the highway. engine still idling, throttle unresponsive."

— 2005 SUBARU LEGACY owner • VEHICLE SPEED CONTROL • Filed 11/15/2020

"While pressing the accelerator there was no response. the car continued at it's normal idle, but pressing on the gas gave no response. i was able to coast to a stop off the road and turn the car off and back on, which fixed the problem the first time."

— 2005 SUBARU LEGACY owner • VEHICLE SPEED CONTROL,FUEL/PROPULSION SYSTEM • Filed 04/16/2015

"I was driving on the highway, and the car seem to loose power, luckily i noticed it, as i was able to cost over to the side of the rode. i own a carmd, and attached it to my car, it gave me code p2138 which means the throttle position sensors (2 of them) not being in agreement."

— 2005 SUBARU LEGACY owner • ELECTRICAL SYSTEM,VEHICLE SPEED CONTROL,FUEL/PROPULSION SYSTEM • Filed 12/22/2012

"For the second time my check engine light has come on and my car has gone into a fail safe mode while driving (eliminating the ability to accelerate). the code the computer provides is p2138, which refers to the throttle position sensors (there are two) not being in agreement."

— 2005 SUBARU LEGACY owner • POWER TRAIN,ELECTRICAL SYSTEM,FUEL/PROPULSION SYSTEM • Filed 12/18/2012

"Car has been very slow to reduce rpms when shifting gears or when stopped (and in neutral) for the past few weeks. today, when pulling into a starbucks, the car surged forward. luckily i have a stick shift and just pushed the clutch in. after surging, the check engine light came on."

— 2005 SUBARU LEGACY owner • ELECTRICAL SYSTEM,VEHICLE SPEED CONTROL,ENGINE • Filed 10/14/2012

Data from NHTSA Vehicle Complaints Database. All reports are filed by vehicle owners directly with the U.S. Department of Transportation.

Common Causes of P2138 on SUBARU LEGACY

41.2%
11.8%
5.9%
5.9%
5.9%

Percentages based on NHTSA complaint component analysis for this vehicle.

Complaint Trend by Year

2005
5
2006
12

What To Do Next

  1. 1
    Check for recalls on YOUR VIN

    Go to nhtsa.gov/recalls and enter your VIN. Free repairs if your vehicle is covered.

  2. 2
    Get a proper diagnosis

    A code alone doesn't tell you the exact failed part. A diagnostic at a shop ($50-$150) pinpoints the root cause before you spend money on parts.

  3. 3
    Compare repair quotes

    Get 2-3 quotes. Dealer vs independent shop prices often differ 30-50% for the same repair.

P2138 on Other Vehicles

Data sourced from the National Highway Traffic Safety Administration (U.S. Department of Transportation) and the SAE J2012 OBD-II standard. Code definitions follow the SAE J2012 / ISO 15031-6 standard. Owner reports are filed directly with NHTSA by vehicle owners. This information is provided for educational purposes only and should not replace professional automotive diagnosis. Always consult a qualified mechanic for vehicle repair decisions.

Last updated: March 2026