Ok.. for those of you who contributed to my original thread I thank you!

https://www.rx7club.com/forum/showth...hreadid=118154

But I finally have some new news.. last night I decided to pull out the fuel pump relay and test it out. When I apply 12V to it I can hear it click, ok hmm.. so I decide to test the voltage at the wiring harness/plug where the relay sits. I find the two prongs that have 12V running between them (on a diagonal to each other) and jumper them with a wire. All of a sudden the fuel pump comes to life louder than ever, I pull the wire and run back to check the pressure on the gauge and it is way up to 85psi. Finally I am making some progress in finding the problem, no matter what I did previously I could not get anything more than 32psi.

But my hunch is that it is not the pump relay that is the problem, I know this because I traded relays with a friend of mine last weekend and saw no improvement. I also tested the fuel pump resistor to .7 ohms, in spec with the manual, and dismissed it as being ok. Now I am thinking twice, it seems like it could only be the fuel pump resistor or the wiring to the relay.. I am not the best at troubleshooting electrical troubles so if anyone has seen this before or has an idea please feel free to contribute! Thanks..

Matt
93 SSM

 

Matt,

Did you unplug the ground on the battery when testing / switching the relay? As I remember the ecu trips-out and thinks that the relay is broken when you unplug it and then afterwards stops trying to turn on the relay until you clear the error code. It happen to me a couple years ago, so I dont remember exactly, but I think it even tripped with the ignition off.

It's nice to see your making progress.

-Ray

Edit: reading your other post for the first time I realize that your running the PFC. Thats means no stock ecu error codes. I still would try resetting the pfc by unplugging the ground for a while to see if it will try to "use" the relay again.