Hi all , need your help again. 1978 280Z. The old gas tank was corroded and gummed up ( car sat for 4 years with gas in it ) I cleaned it out as good as I could,and it ran. However ,to unclog the return line in the tank,I had to break it loose in there. I really don't know what that did,but the car wouldn't run unless tank was basically full.After you burn 7-8 gallons it would start to bog down when you give it the gas like the tank was empty.Fill it up and it would be fine. I took the tank off my parts car , cleaned it out,( much better shape) and put it on.I filled it with gas and it ran fine. I had a cold start problem which ,thanks to JohnH240,was solved (turned out the thermotime and coolant temp.sensors were connected bakwards) It started on 1st crank on several very chilly mornings.NOW,monday morning while on my way to work,it started sputtering and died. I pulled fuel line at filter and it was clogged up. Shook it around and it started and ran o.k.I got a new filter, old one had a pretty good bit of trash ! Next morning , on my way to work, killed again and wouldn't start. I called in ,pulled car to shop (to get it on a rack) and drained tank. I changed the fuel filter again.(NAPA gold) No start. I burned up the starter (Remember those cold start crankings) I bought a new one and it cranks but no start. I pulled the line at the filter,no gas. I went (I know this sounds crazy but I was desperate) and bought a new fuel pump and put it on. Still no gas at the filter. I am getting no gas to the pump. I pulled the line off from the tank to the pump (at the pump) and I blew in it and I could hear the bubbles in the gas tank so I guess it's clear .Did I miss something ? Does anyone know where to go from here. Help....my wife had to bring me to school this morning.