Now I have a copy of Numbchux's write up. He says to use the EJ fuel pump relay. I hung the wires over the fender like he said and plugged everything in to see if it will run. Now all I did was supply the EJ wiring harness with battery voltage. Nothing is spliced into the brat right now. Hence the EA fuel pump relay. With the motor idling, it will run about 2 minutes and die. Turn the key on and off a couple times to prime the FI pump and it fires right back up. Rev's great has no runabilty issues at all. My question is, does the EA fuel pump relay not supply a constant power source to the fuel pump, hense using the EJ fuel pump relay? Im not trying to change the world but if one step can be elimanated... why not.

if you don't have a tach signal run to the EA fuel pump control, then it will not supply power to the pump.

 

You really are gonna want to have the EJ ECU controlling the fuel pump.

Oh got it. I did not know that. That would make sense why the fuel pump would only turn on for a second or two. I did some research on all data and found that the main relay and fuel pump relay are together. Is that true? That must by why numbchux says to use both the main and fuel pump relay from the EJ.

Oh got it. I did not know that. That would make sense why the fuel pump would only turn on for a second or two. I did some research on all data and found that the main relay and fuel pump relay are together. Is that true? That must by why numbchux says to use both the main and fuel pump relay from the EJ.

 

No, the Ignition (main) relay is a 6 wire. closes 2 circuits. Brown

 

the Fuel pump relay is one of the simple round 4 pole ones used for everthing in subies.

 

but they are near eachother in the harness, and IIRC, the Ignition relay passes the signal (coil) volts to the Fuel relay.....although the relay doesn't close until the ECU supplies the ground.

Edited April 4, 201015 yr by Gloyale

I did some research on all data and found that the main relay and fuel pump relay are together.

 

I was talking about the EA81.

 

I am having a problem with the fuel pump relay not getting a gound signal. I had this problem when I striped the harness down. I know it was good before I did the strip. Its ran good. Both of the small wires still go to the ECU and the bigger yellow wire gets battery voltage. But still no voltage coming out of the Big bk/bl wire.

OK well I went out and did some tests on the fuel pump relay. The ECU is sending the ground signal. When battery votage is supplied to the ECU, I get 1 second of no power (ground) from plug F47,pin 23. Which is the way is should be. Also get battery voltage at pin 2 of fuel pump relay when key is on. I still dont have any power coming out of the black/red wire to the fuel pump. The big solid yellow wire out of the relay is slpiced to the same solid yellow wires from the main relay. Should these have contant power also?

 

When I look at Numbchux write up on how the wiring should be, I see that pin 2 & 3 should be spliced together out of the fuel pump relay and then spliced into the yellow/red wires out of the Main relay. Is this what I am suppose to do?