Its been over a year now after my engine was rebuilt and installed everything seemed to work out okay until I got caught up in a fuel injector nightmare. I was recently trying to follow up on a thread I wrote a while back but can't seem to find it, about the issue I have at hand.

Two freaking wires go to each primary injector, and are grounded out and pulsed at the ecu. But god damn! It has been harder then hell getting these injectors to cooperate. I have tried to study as many diagrams as I can to get a better understanding of how our injectors work in order to find a possible short. I have repaired the entire wiring harness only to have the car run for a short period and then back to the same ****! I moved a few things and then the car ran again, I added an aftermarket temperature gauge and installed the parts back onto the car and apparently something got loose or disconnected and now my Injectors will not spray again. What I need is some solid information on how to diagnose why my injectors aren't spraying. What I need to know is exactly what wires are involved in the injector functionability. I know that the two wires that come from each primary injector go into the ecu and I am getting continuity from each wire all the way to the ecu, and from there that is about all I can source. So does the ecu ground the injectors out internally, or through an external wire. Are there any wires at the block or anywhere else that may have an influence on the grounding process. I can ground out the injectors to the battery and they will spray. I'm gonna continue to work on the car and see what I can find out. The damn wiring harnesses are piece of **** and a half in these cars, and the cost to replaces them I might as well buy a whole new motor with harness.


Geeeseee to freaking injectors and an assload of GRIEF!!!!!!!!!!!!!!

 

Each injector has 2 wires - one is 12v that is always there with the ignition key on. There is a 30a EGI fuse under the hood that is for this circuit - from there it goes to the EGI relay, then splits to each injector. The black/yellow stripe wire is the 12v.

The second wire is the wire going straight from the injector to the ECU. The ECU "taps" the wire to ground to make the injector fire.

That's pretty much it.

How do you know that it's the problem?

Dale

 

Is the fuel pump priming?

 

It seems nearly impossible to soundscope the injectors, but It's the injectors not grounding out, that I am sure of, but for what reasons I cannot locate.

No, the fuel pump will not prime when grounded either @ the diagnosis box.

When I take the plenum off and pour some fuel in the ports the car will start right up, or if I ground the injectors out manually it will start up and of course die out due to fuel starvation.

Dale,

So the 12v wire is supplied by the circuit relay and egi relay, which also controlls the fuel pump?, With ignition switch to the on position testing the power at this wire @ the injector does bring up 12v, so it seem everything up until this point is working properly.

Now when it comes to the second wire that is to be grounded out by the ecu, I can ground it out manually @ the individual injector and the injector will spray. I was thinking of running this wire outside of the harness bulk, and just soldering it in at the ecu, do you think this would make any difference. There is continuety from the injectors all the way to the ecu.

During the repair of the wiring harness, I did have to solder some spots in the harness, but I don't think this would have any effect on the current flow, as I mentioned it worked like this for over a couple months.

 

Sounds like you have a problem with the ecu or the harness. Did you test the injectors themselves? What kind of setup are you running?

 

Id say it sounds like the ECU ,,, you have checked the wires all the way from the injectors to the ECU so it isnt the wires,,, ,,,, and u have grounded the injectors to confirm that basically they open and close so id say the injectors are working ok. See if you can borrow a standard ECU of someone close to you and switch it in to confirm if yours is ok or not.

 

Has this been resolved??? If so, what was the issue?