I have a 2008 legacy GT. It was having random very hard shifts and random P1710 fault code. 99.9% of the time it drove smoothly. I noticed that these faults occurred under hard acceleration or on inclines.
Research led me to " turbine speed 2 sensor ", this being a Hall effect transducer which incorporates a transistor sensor component. Often when transistors begin to fail it is heat related, so I reduced the oil level and found that there were no more fault codes but I still had the odd random shift. Which confirmed the sensor was overheating from the oil.
Subaru's fix for this known problem is to replace the valve body with an upgraded version.
I then removed the valve body, detached the sensor, fitted a generic 1/2" Hall effect [$55] sensor in exactly the same position and height to the valve body. I solder joined the pwr/grd/ signal wires to the harness.
To date after 9 weeks, the car drives like new, no hard shifts no fault codes.
Research led me to " turbine speed 2 sensor ", this being a Hall effect transducer which incorporates a transistor sensor component. Often when transistors begin to fail it is heat related, so I reduced the oil level and found that there were no more fault codes but I still had the odd random shift. Which confirmed the sensor was overheating from the oil.
Subaru's fix for this known problem is to replace the valve body with an upgraded version.
I then removed the valve body, detached the sensor, fitted a generic 1/2" Hall effect [$55] sensor in exactly the same position and height to the valve body. I solder joined the pwr/grd/ signal wires to the harness.
To date after 9 weeks, the car drives like new, no hard shifts no fault codes.
