Help with these issues A/C....Vacum Lines....and sputtering

[dalesdakota]

I recently purchased a really nice 99 Chevy Astro 2 wheel drive van......I have three issues with it that I hope someone can help me with.......#1 Van wants to sputter when excellearating about 30-40 mph but runs great before and after that speed.....#2. I need a picture of where ALL the vacum lines are located and where they run to and from on motor ( heater box flaps in dash are not moving to shift air flow from flooor to windsield or anywhere else ) and finally #3. My A/C compressor has a plug that I found melted but cant find out where it went to nor the wires that got melted I will try and attach pictures of the plug any help on these issues will be greatly appreciated.