It did have a linkage attached that stumped me as well. The shaft that the linkage is rivited to pulls out of the TPS unit without any means of retaining it in place. once you pull the the shaft then you can very carefully split the plastic housing and expose the electrical contacts. Be careful not the bend the tiny metal fingers that make up the potentiometer - they are very delicate. I broke one but mine still worked after reassembly. I cleaned it with some contact cleaner and then applied vaseline (clear) grease to the contact surface. worked for the remainder of the summer - fingers crossed. If you post a picture of your assembly I can tell you if it is the same as mine. Judging by your symptoms, it sounds like the same problem.
I saw your post about the TPS that you disassembled and cleaned. My 06 X45 TPS started acting up would only work at idle unless you turn off the motor and restart. When you removed yours did it have a 2 1/2 inch piece of linkage that is spring loaded and riveted to it? I can see how it comes a part will the spring stay in place when I open it up? What did you clean and did you re-grease it and with what type of grease. Thank you for any info. you can give me. Stuart