Hello, I have read several dozen threads on the subject of fuel pump, but nothing that has helped yet, so thought I would tap into the community.
1991 RX-7 NA

I just rebuilt the engine to include replacing every vacuum hose. I pulled the fuel tank and cleaned it out, replaced the strainer, and bench tested the fuel pump, but the pump isn't getting any power.

Here are all the troubleshooting steps I have done:
- Placed a jumper in the yellow connector
- Tested the fuel pump relay/resister (Tested good)
- Tested the circuit opening relay voltage with and without the jumper (Tested good)
- Tested the circuit opening relay for continuity (Tested good)
**Update**
- Tested the fuel pressure using the external 12V power supply. Pump holds roughly 55-60 psi at the fuel pump unit

Here is where it gets interesting... I connected a 12V power source to the pump and the system pressurizes, and the engine will crank, but will not stay running.

Any ideas?

 

welcome to the board.

have you checked the AFM?

maybe test the pump like you did, with the external 12v, and then prop the AFM door open and see if it runs then.

 

I will give that a try...thanks

 

diabolical1, that did the trick. Its cranked right up and idles pretty high, but now I can start setting the crank angle

Does that mean that the MAF sensor if bad?

 

Or you have a big vacuum leak.