while I was at the Pick n Pull in Edmonton I found a Blazer with a new looking IAC so I figured it was worth grabbing considering the price of a new one. I compared it to the one installed on my Jimmy and like described in another person's thread, the shaft was a lot thicker on the "new" one I picked up. It again made a small difference but nothing drastic. I found the source of the main problem though, the upper intake is leaking. I made a quick fix to last until I replace the gasket with a permatex sealant, making sure to crank the engine over a couple of times without starting it to "suck" a little sealant into the leak without it getting sucked too far. It goes to show you that when a vehicle is neglected a lot of things can be the culprit when in combination.