Testing my used 3-port fuel pump for the first time (along with new hoses, cleaned injectors, etc.). The system won't develop more than 25 psi before the fuel pressure regulator.

I went ahead and clamped the fuel return line after the FPR (to rule out a bad FPR), and then even clamped the "R" port out of the fuel pump to make sure a faulty fuel pump check valve was not to blame - still 25 psi (also, the system holds around 20 psi for an hour while I grab a beer and swear I'm not going to work on the car anymore today).

Am I down to a "bad" pump that just doesn't get up to pressure?

It would appear that way ...................

The Cap'n

I have had a HELL of a time with these fuel pumps. I seem to be fine for now, but i keep an extra pump in the garage.

Here was my most recent thread, it has some great links in there that might help you

http://www.914world.com/bbs2/index.php?sho...20pump&st=0

Godd luck

To close this out (in case someone who is evidently mechanically challenged like myself ends up finding this thread via a search):

Turned out the fuel filter was installed backwards - which causes about a 15 psi pressure drop. My AA fuel pump relocation kit came with a filter for a 2-port fuel pump (12 mm filter connection OUT, 8mm filter connection IN). In my attempts to save hose / adapters, I determined that the large fuel line from the tank must obviously go to the large connector on the filter and the small fuel line from the filter must go to the 8mm connector on the fuel pump inlet. Guess I should have noticed the direction arrow on the filter.

Figured this out a while ago - but just remembered that I didn't post the answer.