I've always had a similar thing when opening the fuel cap with it sucking in a heap for quite a while every time I fill up. I could think of it maybe damaging the fuel pump with it having to work harder against the negative pressure but is there any possible harm further than that? It's on the...
Yeah I've never seen the fuel light come on in my '97 FZJ80R either, but I'm assuming it's the bulb too since it doesn't even light up with the key in accessories on. That or I'm just not game enough to test it lol.