1G Injectors will not pulse. Help!

[MM's Talon]

I need help, my injectors wont pulse at all...
i put the node light on them and nothing.. changed the cas still nothing, changed the power transistor, still nothing, changed the fuel injector risistor, still nothing.. change the fuel pump still nothing, changed the ecu still nothing changed the battery still nothing.. checked every single wire, fuse and relay and still nooooooo pulse, new engine rebuild and first intial start and i came into this problem.. the car hasnt ran since rebuild since this, no upgrades just a fresh engine! please help..

 

[92AWDHX40]

Something you may have done, loose wiring?

 

[MM's Talon]

Where though?

just tried to change the fuel injector relay under the center console and still nothing

 

[Brandon Mau]

Have you checked the fuel relay under the dash next to the ECU?

 

[MM's Talon]

Have you checked the fuel relay under the dash next to the ECU?

Yes, i just did that and still nothing..

 

[rts91tsi]

With everything plugged in and the key in the on position, the factory boost gauge should rise to 0 and you should see the check engine light. Also, you should hear the MFI relay and fuel pump kick on. If not I would say that the ECU is shot and causing the issue.

 

[MM's Talon]

With everything plugged in and the key in the on position, the factory boost gauge should rise to 0 and you should see the check engine light. Also, you should hear the MFI relay and fuel pump kick on. If not I would say that the ECU is shot and causing the issue.

ill see about that, but i tried another ecu and it was running fine before

 

[rts91tsi]

I have literally had an ECU fail while my car was parked for a week. I went to start it, and it wouldn't. No boost gauge, no CEL, and no fuel.

Here is a visual from the service manual that shows how the injector pulses are generated from the ECU. This is what leads me to believe that your issue lies there.

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[MM's Talon]

I have literally had an ECU fail while my car was parked for a week. I went to start it, and it wouldn't. No boost gauge, no CEL, and no fuel.

Here is a visual from the service manual that shows how the injector pulses are generated from the ECU. This is what leads me to believe that your issue lies there.

You must be logged in to view this image or video.

thanks man i appreciate!!

 

[MM's Talon]

Update! i ohm'ed out the ecu to the fuel relay and checked for voltage..

everything ohm'ed out fine. the voltage on pin 103 which should make 12 volts doesnt have 12 volts..

the test i found on alldata said to get the volt meter and put the positive on pin 103 while still plugged in and than put the ground wire from volt meter to a ground and it (should) have 12 volts.. but it does not.. also on my alldata injector wiring diagram is shows a "10a" fuse somewhere in the system that is part of the fuel system and ive went through everything and only found one fuse blown which.. it was a "30a which comes from the fuse box to the main power supply to the battery.. i changed that and i turned the key on, and than i could smell fuel ( had one the injectors out) and realized maybe that worked.. so i plugged the noid light in again ( which before never flashed like it should when the injector is pulsing) and finally got a pulse after cranking it.. the car wanted to start, than i fixed some wiring on one of my injectors that had dry rotted and broke, so i wired a new plug in on, and after checking everything i tried to start it and all of a sudden nothing.. no fire, no pulse again.. no fuses blown. tried a different fuel control relay under the dash.. my other ecu, and the other relay on the back of the fire wall and still nothing.. whats going on?