Gas Cap + EEC System

[SeventyOne]

Hey everyone,

I have a question about the EEC system on my K5 and my gas cap.

I think I have everything hooked up correctly:

• PCV hose from carb to PCV valve "T" on valve cover, hose continues to the vapor canister.
• I have a smaller line running from the timed vacuum port on carb to the vapor can
• And the 3rd port/hose on the vapor can goes to the hardline on the frame rail that goes to the gas tank.

All that said I shut off my engine the other day and noticed a sucking/hissing sound coming from the gas cap until what I assume was all the vacuum releasing. I have a locking gas cap unit like this:


Think i got it from Brothers: https://www.brotherstrucks.com/1967-...tinfo/GCP66FL/

Is the sucking sound normal? Do I have the wrong gas cap?

[SeventyOne]

Anyone? From what I understand I need a non-vented gas cap. Is my gas cap non-vented?

[SeventyOne]

Alright well i'm going to try this cap and see what happens. Bummer I can't find a locking one...

https://www.ecklerstrucks.com/chevy-...step-side.html

[pound41]

I ran a locked gas cap on my blazer for years with no issues. looks the same as the one you have. When the says it may be under pressure when opening to me that means no vented