I've changed the fuel pump becuase I had to push the car home the other night. It's not a very light car. Aside from that I have a new problem. My fuel pressure drops rapidly on shut down. I've done the diagnostics. I pinched the feed line and pressure holds for a while thus eliminating the check valve in the pump. I then pinched the return line and the pressure held. Upon release the fuel pressure droped righ off. So I'm thinking regulator. Just yesterday I had a blown diagphram on the AFPR, so I replaced it and I still have the leak down on the return side. It can't be injectors because the car is running great and fires up instantly, plus I'm not getting any black smoke out the tail pipe. If there was a leaking injector that dropped pressure that fast Im sure Id have a full cylinder of fuel. So what else can it be? Do the actual regulator bodies themselves fail on the fuel rail? I'm not talking about the Black cap with the adjuster screw, I'm talking about the block the Black cap is screwed to.

On a side note, I can't control the pressure with the AFPR either. I seem to have just under 60PSI vacuum removed and the scre backed right off

 

Bump

Im having similar issue's

 

it has to b either ur check valves or ur pressure regulator. those are the only things that have to keep pressure while ur car is off.

 

I am also looking for advice on a similar situation. You say that the regulator or the check valve hold the pressure when the car is off what about the fuel rail to top of injector connection could that also bleed off pressure slowly? I put in Bosch III's and I suspect the top of the injectors may be leaking slowly but can't see any gas. Also where is this check valve located?