Maybe you have something wrong with your cat.

 

Now that I think about it, the seats aren't bolted down though. Guess I can throw some bolts in there. I know there's nothin' wrong w/ my cat. I put the 3" hi-flo cat in myself. I'll hafta check the EVAP canister. What does a replacement cost ?

 

Might change the gas cap first(do the cheap stuff first.)They do wear out.

 

Who knows it might solve your problem.