Injectors not Firing on my SR20DET

[BOWDWN275]

I am having an issue with my injectors not firing. I know I have spark to the spark plugs, so the cam sensor is fine. I have checked for power at the injectors and I have 12v. I am pretty sure that the injectors are grounded thru the ecu but they are just not getting it. Checked continuty from the ecu to the injectors and wires test good.

I was wondering if any one knows why my ecu would not be grounding the injectors?

And just a little heads up, my sr20det is sitting in a Hardbody Truck.

[duffman1278]

Bad ECU??? Try swapping it with one you KNOW is working.

[BOWDWN275]

Well, that is what I am leaning toward, but I have already swapped ECUs. I think I have two bad ECUs. One won't turn the fuel pump on and the other turns the pump on, but won't fire the injectors. Was just wondering if anyone had anything I could check before I send one ECU back. I was thinking I might have missed a ground. Any last feedback before I ship the thing back would be awsome!

[fast_s13]

double check all your grounds

[BOWDWN275]

Ok, still no luck! I have replaced the ECU with a good one, I have replaced the injectors with good ones, I know I am getting 12v to the injectors, wires to the ECU from the injectors test good, and I am getting spark at spark plugs. I am close to throwing a grenade at the project and calling it a day. I hope someone can come up with something I am missing. I am guessing that their is a ground the ECU uses to ground the injectors. I am desperate for some help on this. ANYONE?

[duffman1278]

Recheck your wiring, I had to pull apart my stupid harness twice until I found my issues.

[BOWDWN275]

Ok, bumping to the top with new info. I can fire the truck off by pouring small amounts of fuel into the intake thru a vacuum port. I know the truck will run, it is just that the ecu is not firing the injectors. I have drag tested all the injector related pins at the ecu and respective connectors, and all are good. All related wires have good continuity. I have power to the injectors and I can make all the injectors "click" by suppling ground manually. The injector grounds to the ecu are definitly grounded. This is the second ecu I have tried and I have the same problem out of both. I have no ecu diagnostic codes (flashing 55).

I think that is just about everything. I now have no hair left, because I have pulled it all out. So, if anybody has any ideas as to what is going on, PLEASE let me know. I need help.

[trls063]

your going to feel a little ashamed at yourself, but i did everything you just did, and then gave up. but i thought about not thinking so technically, and switched my fuel lines, the send from the pump is supposed to go into the back of the fuel rail and NOT into the fuel pressure regulator. if that works, and i hope its your problem too cause i know how frustrating it is, please post back up.

[BOWDWN275]

Check. System is good. Still not firing the injectors. thanks for the reply though. I really miss my driving my truck and this is the only thing holding me up. It is so fustrating.

[godzilla34]

did you ever find out what the problem was?? im having the same issue with a 93 240 redtop. im getting fuel to the rail. but the injectors wont fire. i can start the motor with starting fluid but thats as far as it gets. any help would be greatful.

[verted240]

have you figured out what the problem was with why your injectors are not firing or being grounded? i have the exact same problem on my 91 red top sr20det.

[rbforsale]

have you done anything with cas?i had the same problem after a few things.it ended up being a brown wire that whent to the grounds as a signal or something. but also the cas was set wrong.dont ask me how two problems came at once

[rbforsale]

also, are you getting the .5v signal to the injectors?

[nissan_star]

your going to feel a little ashamed at yourself, but i did everything you just did, and then gave up. but i thought about not thinking so technically, and switched my fuel lines, the send from the pump is supposed to go into the back of the fuel rail and NOT into the fuel pressure regulator. if that works, and i hope its your problem too cause i know how frustrating it is, please post back up.

holy sh !t, I have the same problem and my fuel lines are hooked up just like you said, the In line is going straight to the regulator and i never stopped to think about it, wow you might have just saved my day!!!

I <3 NiCO

[Wiring Specialties]

A quick suggestion - certainly check the fuel lines as suggested above. Also, if the start signal is not receiving +12V, the ECU will not fire the injectors. Orange wire on the dash connector.

Good luck.

[vocationalzero]

I had the same issue but all 4 of my injectors were dead

[pathyetic]

Well, I know this a shot in the dark.....cause it's been 4 years since you posted. I've been working on my pathfinder for a week straight now with the exact same problem you had, when I happened upon this post. I was about to go buy an ecu until i did, now I'm back to square 1. Please help if you read this!
Thanks,