I think my IAC is bad because the Idle shakes and when I use the AC and put the Blazer into gear the car goes like I'm giving it some gas, but I'm not, and other times after I get going and try to stop, the engine RPMs get stuck at like 1500 and the car wont stop its like the throttle is held open even when I let off the gas. Also it has a hard time keeping the idle consistent when the AC is on.

Blazer has clean throttle body and I have tried cleaning the IAC port.
Looked for vacuum leaks and found nothing as well.

I'm a new college student and need to spend as little as possible to fix it cause I don"t make to much money so I try to fix things myself but I'm at a lose on this one.

I have a 2000 Chevy Blazer 2wd auto 4.3L Vortec V6.