I had cel for small evap leak awhile back. I thought I found a small slice in the U- shaped hose on top of the canister assembly under the truck, so I ordered one for 8 bucks and replaced it. While inspecting the hose further there wasn't anything wrong with the original hose.
Question is: Whenever I loosen the gas cap now I get a slight pressure release. Is this normal ? It was on my other truck, so I thought when I first got this truck and there was no pressure release, it was abnormal. I don't smell gas, so it seems to be an inward swoosh. Swoosh or no swoosh?
Doesn't do it after sitting for 20 to 50 minutes. Seems to be running better overall, (herky jerky idle) but could be different tps I swapped out, not sure why I had it lying around.

 

Yep. Normal. Especially on warm days.

 

Must of accidently fixed something then because I never heard any pressure release when gassing up until I changed out that hose just recently. I tired a new gas cap last summer but made no difference. Small evap leaks can be as small as .02 to .04 in, so even a loose fit could do it I suppose.