Hello, I have a 88 gta 5.7 all stock

why does everyone refer to this diagram



but the actual diagram under the hood which is different never gets mentioned


which one is correct to follow because my set up is like a combination of three different diagrams.

thank you

 

Hard to say. I can't look inside people's heads and see "why" they do ANYTHING. Hell I can't even do that to MYSELF half the time.

Although, that looks kinda like it was copied out ot the printed FSM; which, keep in mind, is printed at THE VERY BEGINNING of the model year, and any changes that occur DURING the year, don't somehow get fed back into old copies.

Looks to me like the only differences are around the vapor canister.

Post your underhood diagram in the vac lines thread. Might help somebody out someday. Might also help if you told us how yours was plumbed, and maybe we could help you figure out if it's OK, or what.

 

Ok, I will post in the vacuum line section.