That, or
You know that lil jumper at the back, between the sender spigot and the hardline? Check it out. I have seen them installed with gear clamps, one on each side, and snugged up enough to crumple the rubber and then; since it is higher than the fuel level, it doesn't leak fuel, but the pump sucks air in there and eventually fills your bowl with air. If the jumper is also kinked, that just makes it worse.
Tip; when you install gear clamps on the suction side, you need to install 2 per side with the screws staggered 180*, and don't tighten thechit outta them.
The factory had the right idea with the spring type clamps.
