This is starting to get annoying.

When I fill up my gas tank, I open the gas cap (so I can get gas in duh...), there is a huge amount of WHOOSH every time I open it. I also have been getting P0440 and P0446 (both related to EVAP system) repeatly and almost on time (every two weeks)

I replaced the gas cap because I thought that was the problem but it is not, where should I look for clogged lines? Vent lines? Chilton is not helpful at all

what year and trim is Stargazer?

Are you sure you bought the right type of gas cap? They do make non-vented.

My brother works at Napa and I told him I needed a new gas cap and he pushed a few buttons on his magic box and gave me the gas cap so I said ok.

I'll see if it'* vented or not vented