When I put gas in my 2000 Town and Country it starts backfiring or chugging if I speed up too quick.?

I have tried different gas stations, changed the fuel filter had pressures checked and can't figure out why it makes that popping noise. When I press the gas it feels like gas isn't quite getting there it kinda sputters. It has been like this for about 6 months so I was told it probably isn't the fuel pump. My gas gauge has been off since this started so i don't know if it is the same reason but I have twice run out of gas when I had a little over 1/4 tank of gas and gas light wasn't even on yet. any help would be appreciated. Next step at mechanics is they will try and replace the pump and see if that does it. I am a single mother of 3 and don't have the extra cash to cross my fingers and hope that is what the problem is. Please Help!