Turbo72-240 Posted November 12, 2013 Share Posted November 12, 2013 I will start with saying that my 72 240z is a mutt.ill start naming some of the parts on it and will end with the problems I am having. F54 block P90a head N42 intake manifold(egrless) Turbo injectors Na afm 83 dizzy w/ e12-80 module Accel 12v coil Efi wiring harness and ecu from 83 n/a No relays at all in the harness. Thats about it with the stuff that needs mentioned,so now my problem is that I cant get the car to start on its own.it starts up great with ether,but thats not saying much.the ecu is not turning on at all,there is no led light coming on.i followed the wiring diagrams on xenons130 page to the best of my knowledge and snipped anything I though I didnt need.i probably screwed something up with that,but here is everything on the harness..6 injectors,afm,tps, and computer.that is all of the plugs.i have the thick green wire from the ecu to the injectors also going to constant 12v.the harness is grounded on the battery and intake manifold.i have plug 26 I believe going to ignition switched.that is all the power to the computer and there is no response.i have been looking through fsms and diagrams out the ass to no avail.i dont have a "pin 1" that goes to the battery or anything.it doesnt exist on my harness or ecu...as I stated,I am getting it started on ether.so the spark is good and I had to remove the afm temporarily because it restricted the air.but I cant figure out how I wired the ecu wrong,it wont turn on at all. again,the ecu and harness is from an 83 n/a. Any help would be greatly appreciated Quote Link to comment Share on other sites More sharing options...
dexter72 Posted November 13, 2013 Share Posted November 13, 2013 My first question is do you have fuel pressure before the fuel rail??.. Do you have spark when cranking the engine over?. Next if your using the stock 83 wiring harness you need atleast 1 relay for the efi system to work. Maybe 2. I used a similar setup to what you have and i needed 2 relays one for the efi system to work. One relay is blue and the other is green. I used the entire efi harness from ecu to injectors, i spliced it to my 260z wiring harness at the passenger side before the harness goes through the firewall. I ran a separate start wire with a fuseable link to my starter, from the ignition switch. Ran separate wires from the fuel pump relay to the rear fuel pump. You should hear an audible click when you turn the key on before turning the key to crank. You need to go over the wiring diagram again and again, You need to run a separate ignition signal wire for one of the efi relays your missing also. My memory is a little foggy about which relay to run that wire to. I'm really leaning towards your missing relays as your problem. Quote Link to comment Share on other sites More sharing options...
NewZed Posted November 13, 2013 Share Posted November 13, 2013 I think that Pin 18 is the ECU trigger from the coil negative terminal. Page EFEC-80. I would spend all of my time looking only at the diagram on EFEC-80 and make sure that everything that should be connected is, and everything that should have power does. It looks like it covers everything. Don't worry about wire colors just use a meter on the terminals. ECU connector to every component. Be aware that after you get it running with your turbo injectors it might stink like gas and foul plugs, if it stays running, because those are the wrong injectors for the ECU. Quote Link to comment Share on other sites More sharing options...
Turbo72-240 Posted November 13, 2013 Author Share Posted November 13, 2013 I do plan on putting the turbo back on that motor,I just need it running first before I worry about all of that.when I bought the motor,the guy didn't have the turbo harness,so I have to work with what I've got...and is page efec-80 in the fsm?...I have too many guides downloaded.thank you Quote Link to comment Share on other sites More sharing options...
Turbo72-240 Posted November 13, 2013 Author Share Posted November 13, 2013 Sorry dex,I didn't see your comment.but I do have spark while cranking...and when I pulled the ecu harness from the donor car,I didn't find any relays connected to it,I didn't even have the blocks for the relay...I think I may have jumped the gun and cut them off when I was pulling the harness.I was trying to be careful not to miss anything though...right now I'm just trying to het it running.I picked up 2 4 prong relays in hopes that I could wire them up myself,but that is where the wiring diagrams are confusing me.I don't completely understand how the relay is connected.on top of that I found 2 diagrams that show the ecu and fuel pump relay wired differently.at that point I was reading through the "ecu circutry" and " ecu wiring"... Quote Link to comment Share on other sites More sharing options...
dexter72 Posted November 13, 2013 Share Posted November 13, 2013 Ok so you have spark while cranking good. You may not need the relays if you have spark while cranking, getting spark is the hardest part of using the zx harness in an earlier z. Does your fuel pump run when your cranking the engine over??? You can run a fuse linked wire the fuel pump, to run with the key on and while cranking. Do you have good fuel pressure from the hose, coming from the fuel filter???... Quote Link to comment Share on other sites More sharing options...
NewZed Posted November 13, 2013 Share Posted November 13, 2013 is page efec-80 in the fsm?.. Yes, it is. For wiring issues, it's best to use the factory publications, in my opinion. Use 1983 since that's your harness, the EFI harness is essentially independent of the body harness except for power supply. When you see the page you'll understand. http://www.nicoclub.com/FSM/ Quote Link to comment Share on other sites More sharing options...
Turbo72-240 Posted November 13, 2013 Author Share Posted November 13, 2013 For now I have the fuel pump wired to a toggle switch because of me not grabbing the relays or even pigtails for them.so k am getting pressure to the injectors,it has 12v constant to all injectors as well.but no pulse at all.i was able to get the ecu to power on outside of the z by putting pin 25 to + of battery and a random ground from the harness to - of battery.the reason I used pin 25 was because I originally thought it was the power because it was green.that was my mistake,it was for the air temp sensor,but when I did that the ecu light came on and off each time I did that...so im assuming the ecu is if working order somewhat at least.but ive even tried taking all of the wires that require a + feed and put them straight to the battery with no luck.even the switched ignition.i cant get that ecu light on for the life of me.i have actually wired the whole harness going from page ec80 in the fsm.but I cant understand why it isnt turning on.to get it running I had to take the afm out so it didnt starve for air because the afm wasnt budging either...is there any specific pins that can be run straight to the battery for it to definately turn on?...and also,just to test my own theory I tried plugging in the "efi relay" pin straight to the battery in hopes for something,but I still got no response. Quote Link to comment Share on other sites More sharing options...
Turbo72-240 Posted November 13, 2013 Author Share Posted November 13, 2013 Update: I tore the harness back out so I can trace everything and resplice everything.what exactly do I need to have for this 83 na harness and ecu to work on my motor?...I have tried jumping all of the wires that go to the positive side of the battery with a jumper wire and all grounds connected to the neg post on battery.none of them made the ecu led light come on.other than the grounds,I have jumped every wire to see if there is anythi NH at all and the only pin that made the light flicker is pin 21 to the air regulator.i otherwise, I amnot getting any power from ecu at all.please help.again,I dont have any relays hooked up because of my ignorance during the harness removal from the bay.i have 2 4prong universal relays that I bought in hopes I could wire them in somehow.i followed off of the keads from the fsm page ec80 to every connector and I cant get a blip from the ecu at all... Quote Link to comment Share on other sites More sharing options...
NewZed Posted November 13, 2013 Share Posted November 13, 2013 You need to go back and put some spaces and capital letters in those two posts. Effort returned is usually about proportional to effort invested. Too much effort is required to figure out what you're trying to say, none is left for a reply. Your problems will make more sense to you also if you describe them well. I've solved a lot of problems while trying to work up a good description so I could ask a question. In short - your jumble of words is too hard to read. Quote Link to comment Share on other sites More sharing options...
Turbo72-240 Posted November 13, 2013 Author Share Posted November 13, 2013 I do apologize. Long story short, the only way I can get the ecu light to turn on is from the wire to the air regulator. The light only turns on as soon as it is connected, after that it doesn't turn back on. Is there a way that I can wire an efi relay and a fuel pump relay in myself using a 4 prong relay from autozone? Or would I be able to jump past them temporarily to see if I can get it started. I have the harness out of the car again so I can triple check all of the splices and connections, but everything checks out okay. I'm not sure what to do from this point. Quote Link to comment Share on other sites More sharing options...
Turbo72-240 Posted November 13, 2013 Author Share Posted November 13, 2013 Went back to the junkyard and snagged the efi and fuel pump relays along with pigtails.now for rewiring it in,hopefully it works. Quote Link to comment Share on other sites More sharing options...
Turbo72-240 Posted November 14, 2013 Author Share Posted November 14, 2013 Okay,I was just messing around with it and I got it to work...I pot power to pin 35,which goes to the afm,and everything started working.i let it idle,and it did great until I turned it off...im not sure how it kicked the ecu on,but everything is functioning as it should. Just wanted to let everyone know I got it working,I dont know how that did it,but im not complaining.hopefully my car doesnt catch fire now.haha. Thanks for the help everybody.(: Quote Link to comment Share on other sites More sharing options...
dexter72 Posted November 15, 2013 Share Posted November 15, 2013 Good job on getting it running. Now fix up your mutt harness, make sure it has good tight colder spots and connections. Quote Link to comment Share on other sites More sharing options...
Turbo72-240 Posted November 15, 2013 Author Share Posted November 15, 2013 Thank you,the harness is all cleaned up and looks pretty good tucked away.I took it for a test drive and it didn't to terrible,but a new problem did arise. After I got it running,it idled at about 5-600 rpms and it sounded like it was going to stall,but it didn't.I actually saw that the CHTS wasn't plugged in. I pliged it in and the idle went up to 1k,and very smooth. After that I took it for another test drive and this time it was horrible.it was spuddering really bad on throttle and barely wanted to go anywhere. So I played around with it again and took the and out of the intake system(but still left it plugged in,it wouldn't run at all unplugged).I barely pushed the flapper on and it stalled out. Would that be a cause of a bad afm,or the fact that the ecu is being powered by one of the afms plugs? Thank you guys.I apologize about the jumbled mess,I tried to describe the symptoms the best that I could Quote Link to comment Share on other sites More sharing options...
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