91 Ford F-150 fuel tank problem

duck4twenty

my front fuel tank went out awhile back just got to fixing it but not sure what the problem is. took bed off to get better acces to tanks my rear tank is fine its my front that has the problem. When i turn key and select front tank i hear it prime,I also pulled off the front fuel line from the filter and gas was pouring out fine.It only runs with rear tank selected once i switch to front tank it starts sputtering and dies What could be the issue?

91 f150 xlt lariat 4.9 straight 6

Mr_Shiftright

You'll have to measure the fuel pressure. You can't really tell much from gas pouring from an open line.

duck4twenty

all good it was the fdm unit itself had a leak inside but now my truck wont start with key but can start if i jump the starter to battery. I got a new solenoid and checked all wiring it good and tight, what could it be now??
i turn key all the way right b4 start and everything works all electrical i also here the pump prime as soon as turn to start nothing.