ive rebuilt my xjs from the ground up, totall engine rebuild new transmission (5 speed swap) and now that i am trying to hook the ECU up i cant get the fuel pump to turn on, the computer relaay turns on and there is power to the fuel pump relay i just cant get continuity on the fuel pump relay negative, any thoughts?

 

Yes, tell us more about 5-speed swap please.

 

Since you dont give a year, I will assume it is a HE engine, in an '80's car??.

IF SO.

The "main relay" switches the fuel pump realy ON, BUT, the earth circuit of that relay is ECU controlled. Look at the fuel pump relay socket. You will see an Orange wire, that is the earth wire. If you cut that wire, and earth the socket section, that will remove the ECU from earth control of that relay, including the timer circuit. This will have the fuel pump working whenever the ign is ON, and care will need to be taken if the wiring is left that way. NOT my recomendation, but quite suitable for diagnosis purposes.

If that fails to get power to the pump, then the relay might be fried inside, it does happen. If power is achieved, but still no pump operation, the pump has gone AWOL.

 

LOL@Mish_mish

 

ill tell you guys all about the five speed swap, and post pics once i can diagnose that fuel pump problem and get it running. and im sorry its an 87 xjs