VeiledLt

Hmmm maybe I should test things first before I come on here acting like an idiot... Sorry, I pinched the air hose to the air regulator and my idle returns to normal which if I recall correctly means it is stuck open correct? I have another one which I am about to go swap in and tune the mix for the new ecu and hopefully voila' any help would be awesome though as to if the ECU could have affected my mix. Thanks so much guys for all the help so far to get it to this point! Spencer EDIT: So I swapped air regs and it helped ALOT! however my idle is still a tad high even with my timing almost all the way retarded, anyone have any idea why this could be happening now? aaaand I went to put the dash back in and broke a piece of a-pillar trim...SON OF A... thanks again

So it runs! I had a friend who has been in the biz forever come help me out for a bit and we found that the grounding strap inside the ignition relay that grounds it through the case had snapped inside... and the contacts that cycle it had arced out and become weak. So, we pulled the relay apart, cleaned the contacts, I soldered in a new ground wire and ran it outside the case and BOOM, she runs. So I took her out for a little quick test drive with the dash out and... wow. It runs like hell, an my idle is climbing like nobodies business. When it starts its fine but everytime you apply throttle the idle climbs a little bit, AND its running SUPER rich. Could this be my ECU, its not new its a reman and the place I bought it from (z-specialties) said that it WILL RUN but he said it may run poorly so I have a warranty on it and I am going to take it in and I thinks thats my running rich problem but does anyone have any idea on the idle? TPS seems to be functioning normally and I have a BCDD Deleted Throttle body? Thanks for all the help so far guys, I will be posting pics up here in a bit of what happened to my relay. Spencer \

So, update, relays and fuel pump cycle with the battery charger on 25 amps, looking at fusible links I'm pretty sure, when the stores open tomorrow I'm going to go and get one of those fuse block replacement ones as recommended by atlanticz and try that out. So spark tested, spark is good however the noid light is showing nothing, my injectors are NOT cycling and the hot wire/power to the ECU, Pin 10 coming from the EFI relay is cold. I could be wrong but nearest I can tell that's the power wire. Now I have tested and retested my EFI relay but I suppose something could still be wrong with it. Other then those two problems though it should start. Please somebody have any idea?

So I'm back with my car and my FSM. Turns out the AFM is on the wiring diagram but your right Daeron and the 78 manual lists a testing procedure so I will be trying that. Still don't have any ideas why my relays WILL NOT cycle without the battery charger on 500amps.... anyone have any ideas on that one? Please? haha, well anyway, the fuel pump control relay also shows a fusible link between B+ and the fuel pump relay, where is this fusible link? And yes NewZed you are correct, the engine uses the alternator "L" signal and oil pressure only to continue running but NOT to start, says in the FSM its to prevent the fuel pump from pumping in the event of a crash. Anywho, I'll be working on the Z all day so if anyone has any input I'd love to hear it! Thanks in advance and Happy Easter Spencer

So I'm not with the car right now but I have Sunday off so I'll be working on it then but I can tell you guys a few things right off the bat that I KNOW from working on it so damn much. So when the key is on I WILL CHECK to see if I have power at the ECU I think it shows pin 10 in the EFI bible Ill check the FSM to see if thats the same. The car has zero fuel pressure as the fuel pump is not cycling. Spark looks good from a visual gap to the end of the plug but I will check and see with a REAL tester haha. And using a noid light, damn thats a good idea, thank you! Aaand the wire to the alternator, well I know I have one, where is this fusible link your talking about though? And I think the alternator "L" signal as it is referred to in the FSM/EFI bible is only required to KEEP the fuel pump running not to start it but I could be wrong, is that what you were thinking Jaybee? Thanks for all the help guys I'm hopeful we'll get this figured out this weekend, thanks for the great ideas Nosebleedz, any more info you guys need just let me know! THanks again! Spencer

I'm not trying to swap parts blind man it just sucks.... I don't know what else to do and I feel lost as hell and it sucks... I mean it can only be the wiring or components and the wiring has checked out so far for continuity and resistance unless I have a fat voltage drop somewhere. Are there any fusible links that are covered or hard to find? and as far as components go I mean hell, I have a new ECU and the only other things on that circuit are the relays and they check out, aside from the afm which you mentioned but on the engine fuel wiring diagram in the FSM it doesn't show the AFM, I am NOT saying I dont believe or trust you Daeron lol I just don't know where/what terminals to look for and what to look for on them? Sorry for all the sweeping questions but I'm just lost guys, thanks in advance and I know I'll figure this out with your help eventually! Thanks again! Spencer.

Just had a conversation with one of the other techs at work and we were thinking it sounds like excessive resistance somewhere between B+ and maybe the EFI relay or the Ignition relay since it goes from there to the fuel pump relay AND the EFI relay unless I'm reading my diagram backwards? Im just curious as to what could cause that excessive resistance? Is there a fusible link I could be missing other then the 4 under the covered boxes attached to the relay cover and the 2 wire combo that clips to the other side?

Is it possible your dist. drive spindle is clocked wrong? Like maybe a tooth off? Try setting your motor at TDC 1 and removing the distributor and looking at where the spindle comes up in that housing, I'm not with my FSM but I believe spec is like 5* from the center line with the smaller portion of the spindle facing towards the front of the car? Hope that helps! Spencer

So I got a new ECU, it was around $150 for a 3 month warranty. Plugged it in andddddddddddd nothing. Lame. Well on to the next thing. However, when I was cranking it over it got a little tired from spinning the starter motor so I hooked the battery charger up to it and put it on START so roughly 500amps to the battery. And, all of my relays cycled! So I am thinking excessive resistance on the positive side maybe between B+ and my relays? But where? I have checked all the fusible links and the wiring between the battery and those relays is.... 18 inches long....maybe? I feel like I am missing something super obvious, thanks for the help so far guys I feel like Its almost there! Spencer

Hey thanks for the help so far guys. Daeron as to what your talking about with the AFM I believe you are indeed correct and I wanted to see so I continuity checked the start signal to the relay wire (pin 4 at ECU) and the relay back to the ECU wire (pin 10) and had full continuity and avg. resistance readings at both and I THINK that if I were sending a signal to the relay I should be getting something on one of those wires and they are both getting zero voltage. I am currently in the process of attempting to track down an ECU for the car to try it out, any idea on a ballpark figure for whats reasonable? I was thinking $350ish for a new or $150ish for a used? Thanks again for the help guys hopefully I can get this figured out today I have to go back to work tomorrow haha. Spencer

So I know everyone has L28 efi questions and I'm sorry for troubling everyone with another one but I am stumped honestly. I have the EFI bible and my 78 FSM on my computer and have been pouring over them for the better part of two weeks and working on my car when I have days off, like today. Anyway, originally my car had no spark, I ended up replacing the ignition pick up sensor in the dist, the coil and the transistor ignition module. As soon as I had spark, my fuel pump stop cycling. I know this because it is quite loud and I heard it every other crank except for the crank when I got spark, now, no fuel. I have found that my fuel pump relay if fed by my EFI relay and the EFI relay is NOT cycling, it is making no audible noise whatsoever, I have however tested it based on procedures found in the FSM for energized and non energized testing and it is fine as are both fuel pump relays. Now as I understand it the EFI relay feeds the fuel pump control relay based off of a power directly from B+ and a "on" power from the ignition switch (key). My signal from my ignition switch is not making it to the relay. Power is coming from the switch and to the sub harness that runs along the firewall to the relay but not THROUGH the harness. Now I find it strange that randomly my harness would fail after being fine for so long and as soon as I get spark it fails, possible but seemingly HIGHLY unlikely. As far as information goes the car is ALL stock, wiring has never been touched. So I am curious is there a fusible link I am missing? Does this signal go through the ECU then to the relay? I have measured for "start" signal at the ECU 32pin connector and gotten it but I am getting NO signal on the pin to test the fuel pump relay circuit. Did I perhaps test my relay wrong? I have a new one on order but it seems odd that a relay would fail as soon as I get spark. Anyway... Sorry for the novel everyone but I just need some fresh ideas! You guys have always been a huge help and I would like to thank all of you in advance for any input you might have! Spencer Also I work at an Audi dealership so if anyone needs Audi help, let me know! EDIT: Just jumped fuel pump wire at the air regulator and the fuel pump cycles. I am leaning towards needing a new ECU? Does the start signal from the ignition switch I referred too run through the ECU?

Which module are you referring to the one in the interior under the dash near the fuse panel? And mine just started yesterday so hopefully I can limp it to and from work this week until I can get to a pull apart on the weekend how long did yours hold out? Thanks for the help guys!

Yeah, sorry about that... I really didn't mean to do that, so I have a 78' 280z and yes everything works fine, cranks I can hear everything as usual, compression builds perfectly, plugs are not fouled, fuel pressure is good, fuel filter has only around 10k or less on it. I work on cars for a living but the Z has been...difficult for me and being my daily driver I can only afford so many extended repairs on it. And when it starts it runs fine, no hesitation or bogging of any kind. Again sorry for being short in my original post and thank you in advance for any help anyone can shed on the subject!

Just went out and checked the car has source voltage at the positive terminal on the coil even in a no spark situation. Could an ignition coil cause intermittent starting? But as I understand a coil to operate the only malfunction that would cause no spark would be a break in the wire and I would not think that problem to be intermittent?

So I've been searching all of last night and most of this morning and have decided that I may need some help from the best, you guys. Yesterday my car chose not to start on the first key on, not surprising as I have been having an issue with vapor locking as of late and I just assumed it was the same, so I let the car sit for another ten minutes or so and tried again, no luck. However with repeated attempts it did start. It did not sputter to life it came right on. So I have been looking and think it is either a faulty ignition relay, ignition switch or primary coil because the problem is hit or miss sometimes the car starts right up (rare) and some times it takes 20 key on procedures to hit spark. I've checked for spark at the plugs and back and I'm getting nothing all the way back to the coil. Any thoughts? Thanks in advance guys! Spencer