I have a 1990 Deville with a throttle body that may need to be rebuilt. It does not close on its own. The unit is clean and is getting removed to see if the blades or shaft is sticking. My mechanic said you can send these out to be rebuilt, is that true? and is it worth it to fix it properly. Can I get one at a junk yard and try my chances. ISC is going to be replaced but he does not think that will solve the problem completely. I read this site often and feel good about my mechanic and doing good work. My question is are there resources out there on rebuilding these units if need be. I live in the NW part of the country. I plan on keeping the car for a while. The price to rebuild them is $400 + and he said Gm does not make new ones.