l just went thru this the last couple of days with my RC / all new line / it got a little better / new fuel pump /it got some what better / fixed it for good last night / cut a hole in the floor to get to the sending unit / the sending unit elbow looked like a flute/ [crude fix - not for children] l broke the elbow off and used copper FRIG ice maker tubing shoved as far down into the sender as l could get / put some epoxy around it and hooked up the gas line / fuel problems ALL fixed / it was driving me nuts all week