https://www.performancetrucks.net/fo...6&postcount=33

I'm looking at the second pic in this older post of yours. Behind & to the right of the throttle body is a brass plug, where the EGR tube would go. Just below that, I see a hole of some type.(at least it looks like a hole from Alaska)

What do I win if that's it?

 

I had the same type issue when I put the whipple on my jeep. I swore there was no vac leak and did the same thing put my finger over the IAC oppening and it idle fine. so then I took a heavy piece of cardboard and put it over the entire TB and guess what it still ran thus a vac leak. It was in a strange place but it was there. The othe thing is that you may have the IAC wired backwards and instead of closing to keep the idle down it may be opening. Just my 2 cents

 

I just looked at my truck, that's just an empty bolt hole, unused. But keep looking for your vacuum leak.

 

Tried that motor died. But if I can not find it this weekend going to pull the blower. Were was your leak?

 

I will be back on it. Thanks a lot guys