1998 Audi A6 2.8 Quattro wagon
 

(1998 Audi A6 2.8 Quattro wagon)
Radio won't work and I can't seem to find out if a fuse is blown because I don't know the diagram for the fuses. Also I had a OBD 2 test done and it read that my throttle position sensor is going. Is there a site where I can get one cheaper than 250 dollars?