Thread: engine not starting....ugh

ok..as the title says...a few months ago the car started fine...now all of a sudden it wont start...drained tank...new gas,filter,plugs,wires,cap,button..i thought it mighta been the engine harness cause i had to fix it since it was hacked when i got it and i had to fix it....changed harness from a 93 to the 91 and still no start...it turns over fine...i have no idea...any help would be great guys

Well you only need 3 things to make your engine run. Fuel, air, spark. Air is a given, so check for fuel, and spark. If you aren't getting spark it may be the dizzy, coil, of ignitor. I remember trying an ignitor from a 94 ser in my 92 nx and it wouldn't fire. If you have the harness installed correctly from the 91 use the ignitor from your 93 and see if that gives you spark. You can test your dizzy and injectors by unbolting it, while leaving all of the wires plugged in, and turning it by hand. Turn the ignition switch on, and while slowly spinning the dizzy listen for each injector to pop.

Dist is fine...put diff fuel rail...diff fuel pump...diff coil and every sensor on the whole motor ...even changed mafs...any new ideas??

well, just changing the components won't really help, you need to test and diagnose the problem rather than throw parts at it.

Pull up the FSM and do basic checks on the ignition and fuel systems and post up your results. tswii gave you a great first step breakdown that you seem to have disregarded.

Yeah all of the diagnostics are in EF & EC IIRC. Have you checked all of the fuses, and fusable links? You got a fuse box under the hood too. I believe there was a thread I read not to long ago about a car not starting. I'm trying to remember, but I think it was some fuse, or link that popped for the ignition circuit. Another member pointed that out, after the OP had done alot of the same stuff you have, and that was it. Since you said the harness was hacked, and you had to swap it, something may have shorted at some point, and popped a fuse. Did you disconnect the Neg. battery post before unplugging stuff? Because if you didn't, even with the ignition switch off, you can still short stuff.

when my nx stopped starting randomly, it was the fuel pump. my neighbors camaro wouldnt start. it was the HV terminal on his ignition coil got corroded... had to pull the plug to even see that.

I will try all this...thanx everyone

ok...maybe i forgot to put everything on here or im just a idiot...maybe both...here we go..i have spark to the plugs...fuel all the way...u already saw what ive changed... i also changed the engine fuse in bay...the 91 and 93 harnesses are almost the same...theres 1 plug that is diff... it has the thick black and red wire in it...i had to cut the 93 plug off and had to put the 91 plug onto it.. i have em connected right and tight...theres been so much fuel in there that theres a ton in the oil and if i try and start it for 2 minutes one day and come back out the next it backfires thru the exhaust... is there anyway that it might have jumped time?? IF IM NOT UNDERSTANDING ANYTHING JUST DUMB IT DOWN FOR ME...LOL

do you even know if the pin outs are the same for the wire harness you switched it too? I would have started with that first and then traced it back through.

Are you using the same ecu?I was going through a similar issue it turns out I burned out two of the ground points in the ecu. Pull it open the case and look for any burned or broken leads closest to the harness plug ,