billseph Posted December 21, 2011 Share Posted December 21, 2011 So I'm working on getting my 81 L28ET swap into my 71 S30 going. Getting Fuel has been no problem...I've got power to fuel pump relay for 5 sec. In on and while cranking via pin 16 from ECU...also injectors seem to be working snice they're flooded with fuel from cranking with no spark. Anyways I've got no spark as the title says...I swear it's all hooked up right, but it obviously must not be or I've got a bad component somewhere. So here's the facts..... Pin 9, 27, and 35 all have power in the ignition "on" position and while cranking...GOOD?? Coil + and - have 12 volts in ignition "on" position...seems okay right?? Black/white strip on ignitor the "top of the "T" on the T plug, goes to 12 volt switched Yellow/white strip on ignitor the "vertical on the "T" on the T plug, goes to the yellow/white wire of the ignition harness plug (goes to Pin 5 of ECU as it should) There was a blue and a black wire coming out of the ignitor I have...they were just cut off by someone else, so I ran the black wire (which had 12 volts when T plug on ignitor is plugged in) to Coil +...SOUND RIGHT?? I ran the blue wire to Coil - (it has no power no ground) if it's just left hanging loose. Ignitor/coil bracket are verified to be grounded. Also as a side note, everthing hooked up to 12 volt switched never drops below 10.5 volts during cranking. And I'm running 82 zxt dizzy with internal CAS (followed FSM to get oil pump shaft in correctly) SOOOOOO, question time... My ECU light (green) comes on only with igniton in "on" and turns off while cranking...Should it stay on or be on while not in "on" position??? I've spent hours looking at the wiring diagrams from the FSM's and all my wiring seems right. What do you guys think...I'm hoping an old pro at the swap can point out my error with ease. I'm guessing I just have a wire at the ignitor wrong or something. I've read that the ECU "interrupts" the coil 12 volt signal or something to get the coil to fire...I have no pulsing. THE YELLOW/WHITE WIRE FROM THE IGNITOR HAS 0.07 volts with key in "on" and jumps up to 0.3 volts while cranking...Sound good or bad?? Thanks a ton guys...I know you answer these questions all the time so I did my homework before asking. I'm just stumped. Quote Link to comment Share on other sites More sharing options...
tecreatta Posted December 21, 2011 Share Posted December 21, 2011 Do you have the chts and cold start hooked up correctly if not you'll flood the engine and foul the plugs. It's an issue I've encountered before. Make sure your sensor wiring is correct and and swap in a set of new plugs. Quote Link to comment Share on other sites More sharing options...
billseph Posted December 21, 2011 Author Share Posted December 21, 2011 Thanks for the advice there, but I need to get SPARK. I've just got a #3 plug pulled attached to the spark plug wire so I can see if it's sparking. Only sensor not hooked up is knock...but this shouldn't affect me getting spark. Quote Link to comment Share on other sites More sharing options...
cgsheen Posted December 21, 2011 Share Posted December 21, 2011 Sounds like you've got the coil and ignitor wired correctly. From the ignitor, Black/white goes to + on the coil, Blue goes to - ... There's a second blue that runs off the - pole on the coil and runs to the Tach through the Tach Resistor. (Blue is of course the pulse that's supposed to fire the coil) Black/white to the ignitor is power and Yellow/white is the trigger from the ECU. The ECU controls the spark. It uses the CAS info to determine when to fire the coil. The ignitor is a transistor "amplifier" - it turns (amplifies) the signal from the ECU into something that will cause the coil to fire... I don't know if there's anything in the FSM about how to check the ignitor. It does give the resistance values for the primary and secondary windings of the coil. But it sounds like you should be checking the output of the ignitor (Blue wire) rather than the Yellow/white that is the trigger... The green LED on the ECU is operating correctly. It lights when the IGN is switched to ON, and goes out during cranking or at startup. It won't come on again generally until the engine is warm enough (CHTS over 140 degrees I believe) for the ECU to consider running "closed loop" - then it signals a "Rich" condition being reported by the O2 Sensor. I think I'd double check the dizzy and the CAS signal / wiring and connectors. Actually, wiring and connectors are some of the biggest problem areas for these engines... Check and clean them all. Quote Link to comment Share on other sites More sharing options...
billseph Posted December 21, 2011 Author Share Posted December 21, 2011 Thanks for the reply cgsheen. I went ahead and checked power to the CAS (popped the cap, rotor, and cover plate off the dizzy to check internally)...it got 12 volts...also checked continuity back to the corresponding ECU plugs while I was in there...ALL GOOD. So CAS checked out OK. I checked voltage off the blue wire coming out of the ignitor that would connect to the coil -. Without the blue wire being connected to the coil I got about 1.0 volt with key in "on" and 0.9 volt while cranking. With the blue wire connected to coil - I got 12 volts with key in "on" and around 10.5 volts while cranking. Should I be checking amps or milliamps instead????? Sooooo, after these tests I'm leaning toward BAD IGNITOR...any thoughts. (Also I have cleaned all my connections...have good connections back to ECU for TPS, Air Regulator, Injectors, and CHTS. Buy really none of these should influence SPARK...just the ignitor and CAS, right???) A little background too.......I bought the car off some dude who'd swapped in the 81 zxt motor already...he went by the name Krumm on this site. He had trouble getting spark as well and suspected a bad CAS (crank mounted) so he swapped in a n/a dizzy (3rd page of the good ole' turbo swap into S30 sticky) to "make" it work. This leads me further to suspect a bad ignitor being my (our) root issue with spark. Anyways, now I'm trying to get this swap working PROPERLY so I can swap in my JWT 450 modded ECU. Maybe someone can be so gracious as to run these same tests I just have, or give me pointers on verifying a properly functioning ignitor. I'm so close I can taste it but this "lack of spark" issue has been a huge bummer. I think I'm gonna have to drop the $100 and get a coil/ignitor from the classifieds here on HBZ, but it'd be nice to get confirmation from someone with a zxt or a working swap. Thanks for listening guys...good thing is that all these headaches will just make success so much sweeter!! Quote Link to comment Share on other sites More sharing options...
afbrian13 Posted December 21, 2011 Share Posted December 21, 2011 It sounds to me like a bad ignitor. As long as everything is wired right, thats it. I'd check my notes but I sold the ZXT motor and gave the guy my notes and a step by step writup how to hook it up. They aren't cheap, but at the J/Y alot of 80's nissans like stanza's and pulsar have an ignitor too. Thats what I wired up for less than $5, and it worked great. The transistor nissan used is an odd one. Our circuit repair section and an electronics warehouse couldn't match it, but we were working with the blown one. J/Y is the cheapest option. I fought with mine for a long time before giving in to the ignitor. Good luck. Quote Link to comment Share on other sites More sharing options...
NewZed Posted December 21, 2011 Share Posted December 21, 2011 Seems like one of the Megasquirt coil drivers should work. It would need protection from the elements, proper installation and a decent heat sink, but functionally it's designed for the job. Cheap enough to experiment with also. http://www.diyautotune.com/catalog/bosch-bip373-coil-driver-mod-kit-p-230.html Quote Link to comment Share on other sites More sharing options...
billseph Posted December 21, 2011 Author Share Posted December 21, 2011 That driver looks cool and would work I'm sure, and for less than $10 it would be very cool if someone could get it to work and show us all how to do the mod. However for me, this is one of those situations where I just need to pay up for "plug and play" since I'm a rookie. Maybe one day when I've got it all running properly I can experiment with this...but that's a BIG maybe Quote Link to comment Share on other sites More sharing options...
NewZed Posted December 21, 2011 Share Posted December 21, 2011 Well then, the OReilly Auto web site will show you a list of wrecking yard cars to check - http://www.oreillyauto.com/site/c/detail/IDI0/140148.oap?year=1982&make=Nissan&model=280ZX&vi=1209361&ck=Search_ignition+module!s!control+unit!s!ignitor_1209361_-1&keyword=ignition+module!s!control+unit!s!ignitor Click the Compatibility tab. If the link doesn't work, search "ignition module, that's what the ignitor is listed under. Quote Link to comment Share on other sites More sharing options...
billseph Posted December 21, 2011 Author Share Posted December 21, 2011 Very nice link NewZed...thank you. I'm about 1hr away from any JY's (I'd be going to north Bakersfield, CA or south to Lancaster/Palmdale CA...I'm about 1 hr. from both). I guess if it comes down to it I know what cars to look at now. Just thought of something after I saw the compatible vehicles on that link...will my e12-80 ignition module mounted on the n/a dizzy that had been in the car work??? It's got a T plug to plug into and a green and a red wire coming out of it into the dizzy. What do you think NewZed??? You're like the electric guru around here. Quote Link to comment Share on other sites More sharing options...
billseph Posted December 22, 2011 Author Share Posted December 22, 2011 Nevermind, answered my own question with a no...the e12-80 ignition module is NOT at all going to work. Anyone got a working ignitor/coil bracket they can let go of...I gotta get this thing going. Quote Link to comment Share on other sites More sharing options...
billseph Posted January 1, 2012 Author Share Posted January 1, 2012 Almost forgot to conclude this. Ignitor was indeed bad. I did the HEI upgrade in lieu of replacing the 280zxt ignitor and that baby fired up on the first crank. The HEI upgrade is a nice cheap fix for now...I'll have to see how it turns out in the long run, but this will be a street car that won't be hanging out in the upper RPM range for extended periods, so I'm assuming the HEI will last. As a side note now that I got the 81 electronics lined out plugging everything in for the JWT 450 modded ECU and doing the minor re-wiring was a piece of cake. I've only got to run it for a couple minutes as of today but I'm loving it already...dying to take it for a spin Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.