fuel pressure dropping over time

clementine said

I'm late to the party but what about the isolator line to mechanical gauge being burped? Would air in that line cause this issue....

#shootingfromthehip

sounds like you have it figured with the supply issue.

Click to expand...

I don't think it will.....I'm no physicist, but it would be the same as having air in an oil pressure gauge line. The oil pressure gauge still reads correctly. The air in the line compresses some I am sure, but the gauge will read right since the air only compresses to a certain point. I imagine the fuel gauge is the same.