my jimmy wont start unless it gets a wiff of carb cleaner where does blow by happen in the tank i replaced the pump 4 times but never replaced the unit that the pump slides into new $500 spider from gm dealer less than 5000 on that part

need to check to make sure system holds pressure w/engine off
the unit your refering to is call sender unit,believe it just controls fuel gauge
but may rust & cause a leak, check & see if your holding pressure