hi have just brought my first car that runs gas its a 2000 fairlane ghia 5l its a bit rough starting on gas but runs an drives fine also it backfired on start up yesterday while allready warmed up is this normal and is there anything i should know about running gas

It's not normal at all.
My falcon starts on gas perfectly fine with no running issues. People in the very southern part of the country may have issues on really cold days though.


Backfiring is not normal either, It needs a tune.
Give the usual plugs and leads, Use plugs with a .8 or .9 gap and then have it tuned.
I can give you the number of a guy in Albion if thats not to far away from you.