The car- 1986 RX7, Stock S4 EFI, manual, NA.
The problem- Fuel pump runs, sometimes. Does not get consistent voltage, generally jumping around from 3-10V. Fuel pump works fine and car runs well when a wire is run straight from the battery.
Anybody have any idea where to look before I just go ahead and put in a relay to provide power to the fuel pump?
Bad ground?
In reply to NGTD:
If it is I can't find it, I've been all over the car looking at the wiring/grounds and have recently cleaned all of the ones I could find.
What about the MAF- potential cause?
Change the relay 1st. Bad contacts can do this.
I would start by bypassing the relay.
Been a lot of years, but as I recall, a full re-wire on the FC fuel pump is considered a must-do.
In reply to 1988RedT2:
THIS is the sort of advice I come here for- if it's going to keep me from a DNF, I consider the work to rewire cheap insurance. The only DNF in the car's logbook is for a fuel pump failure 
I seem to recall that the stock pump has a 2 stage voltage regulator, lower voltage for lower engine loads to reduce fuel getting recirculated back to the tank. For your use, a re-wire would be the way to go.
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