Just wanted to document what I just ran across for when others come across this.
I put a T2 controller in my 2002 and got a -08 when I tried to test it. When I gave it throttle it would give -11 error.
I tracked it down to 2 pins on the P23 connector. Pins 7 and 8 could be wiggled ever so slightly and that would change the error code and sometimes it would go away. After I cleaned the P23 pins and sprayed contact cleaner in the connector the problem persisted so I released the double latched red portion of the 23pin conenctor then grabbed pin 8 wire and turned it 90 deg and was able to pull it out. Testing it on the P23 connector pins it was very loose so I used a small pointed needle and gently pushed each of the 3 spring clips inward a tiny bit. These 3 springs are seen on the sides if the socket connector. Tested and it was snug again. I tested all other sockets in the p23 connector and fixed them too.
No more -08 error nor -11 error. YMMV