You're right! It's a newb question but that's why we're all here...no learn and share.
Yes the tubing you're referring to is the pressure line from your exhaust to your tank. If you want you can buy all sorts of different color tubing to change it out with so you can't see the yellowing. Remember that the length is important. I think the piece it comes with is nine inch.
ORIGINAL: twysted
well this may be a newb question but im gonna ask anyway
is it normal for the tube that goes between the pipe and gastank to be Yellow ???