My friend has 2003 nissan sentra spec-v r (2.5l I4). What's with these cars not having a replaceable fuel filter? or does auto shops just not list it anywhere?

id bet on the latter.
a car without a replaceable or at least serviceable fuel filter is a ticking bomb.
go to your local dealer. it shouldnt be more than 20 bucks

on autozone's website, when i look up the fuel filter it says non serviceable part, does that mean it's a lifetime filter

oooohhhh i just read up and apparently there is no filter, but nissan dealerships offer fuel injection servicing for like 100 bucks or something. i feel awkward trying to tell you all this info since i dont even have a spec, so just go ask your dealership what needs to be done as far as maintanence. try to ask one of the mechanics, sometimes the parts counter people are idiots