I should mention that this is my nephew's Mazda3. He called this afternoon and asked me what I thought it was and I said I'd converse with the 3 gurus.

He said it will operate just fine when he's running around town and on short trips, but when he takes a long trip and he stops for gas, after filling up he has trouble starting the car. He said it will finally start after about the 5th or 6th try. Anyone have problems with this before? I'm leaning towards it being a fuel issue but I have NO idea where to start with this one and I figured some of you owners may have encountered this before. Thanks in advance!

have him start with replacing the fuel filter. That is what it sounds like to me.

I would start with spark plugs, maybe pulling/reseating all of them
When I had a similar problem in my old car, it turned out to be the starter-relay (which I found out after replacing the starter/plugs)

is it slow tunring over, or jjust wont catch but turns normal?

depending on that might help with diagnosis. if its after long trips, it might be heat related, as in something is getting too warm. i'd check spark and see what thats like. i know some 3's have issues with the coil packs, so thats a possibility.

i would think witha fuel filter it would have issues while driving as well, as in sputtering and what not.

gas cap? i mean if its after a fill up at a gas station

Cool, thanks guys. I told him to check for spark, maybe change the fuel filter, check to make sure the alternator is charging the battery, check the gas cap, etc. Although even all those things don't seem likely because if any of them were faulty I would think he would have problems around town too. Not sure.

He just told me it has 79k miles and it cranks hard every time but it takes a lot to get it started, and when it does finally start it shudders pretty hard.

Sounds like Lyssa's issues, with the purge valve and all that non sense, actually exactly like that.

OK I'll check with her. Thanks!