Checked prime fuel pressure today and only got 25 psi. I had my daughter roll the key forward as I clamped the return line and saw no change in psi. If I can get it running it runs at 38 psi, but it does not want to start. Is the 25 psi prime pressure too low? From what I can tell the pump is shot. I even changed the fuel filter again thinking it could be clogged. The car runs rich when it runs at all, could this be the compensation for the lack of fuel flow by means of enrichment? The injectors are NOT leaking because I removed the rail and watched. Is it possible that the injectors are just not getting enough psi or volume to atomize properly; thus just a weak pouring stream into the cylinder? Please help, I don't have money to dump into this car right now (damn college tuition).

 

While I'm not 100% sure it's your problem, it does sound like you've got a weak fuel pump. When you got the reading of 38 psi, did you have the vacuum line to the fuel pressure regulator disconnected? When the vacuum line is hooked up it'll drop the fuel pressure somewhat. The correct way to check the fuel pressure is to have the vacuum hose disconnected and plugged, and the motor running. With no vacuum supply to the regulator, you should be running about 42-45 psi with a good pump. If the psi is less than 40 with no vacuum on the regulator, chances are you do have a weak pump.

 

The 38 psi. is with the vacuum supply hooked up. When I pull it the gauge reads about 44. The thing is that the thing is only priming 25 psi. now. I think the pump is just failing.

 

could be a leaking pulse damper as well.

 

Yep I thought if that as well. Gonna remove the pulsator and replace with EFI hose. Might as well do a pump while I'm in there. Wish I could make an access hole but it's a convertible and supports are in the way. Should prove to be a real p.i.t.a. to do it.

 

The hardest part is getting the fillet tube out of the body. Jack it way up.
and the pump always fails with a full tank !!

 

Haha. Lucky enough she's almost on empty!