I quess I dont understand. My truck and the guys I run with cant tell if they are getting low on fuel. maybe we are talking about two defferant things. I mean when the tank has a few drops left well yes of course I can tell it might sputter and lean up for a split second before it dies. but I cant see how there is a defferance between a full tank or a tank that is 1/4 or 1/8 full. the tank is pressureised on a constant pressure. which means constant fuel flow. if an air bubble does happen to get in the line once it reaches the spray bar it will blow out so fast it wont make a defferance. unless it is a big air pocket or a bunch of them in a row.