jimbo5670 Posted July 9, 2006 Share Posted July 9, 2006 i have a 72 240z that is getting a 82 or 83 l28et and have decided to go the megasquirt route. Im tring to get it to run on the ground before I pull the old motor from the car. My question involves the bare minimum to get spark from running the 4 pin HEI, the 82 or 83 coil and dist. what i have tried is to hook it up according to the FAQ diagram without the step down things i have the... red strait to the battery (12v) white directly to the tach wire on the 2.2 MS unit (pin 24) green bent off to the side black grounded to the intake manifold on the HEI i had... Fidle (pin 30) right to G on the HEI W on HEI grounded and B and C to + and - on the coil cranked it and no spark from the coil, at all anyone that can think of anything that im doing wrong, pleaseee help thanks, matt Quote Link to comment Share on other sites More sharing options...
Mack Posted July 9, 2006 Share Posted July 9, 2006 what stepdown things are you talking about? is yoru HEI new or did you pull one out of the junkyard? HEI units dont last long when you get them from the junkyard and are actually usually bad. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted July 9, 2006 Share Posted July 9, 2006 You need the two resistors installed like the sticky diagram shows if you don't already have that. Quote Link to comment Share on other sites More sharing options...
seth Posted July 9, 2006 Share Posted July 9, 2006 Ya I had trouble with the HEI too... I eventually gave up and went to a MSD. And i am much happier. Quote Link to comment Share on other sites More sharing options...
jimbo5670 Posted July 9, 2006 Author Share Posted July 9, 2006 the diagram looks like i am taking a 12v from the battery, running a 1k resister, then t connecting it to the megasquirt trigger line, or does that represent something else, or is it ran inline and there is no 12v feed? Quote Link to comment Share on other sites More sharing options...
badjuju Posted July 9, 2006 Share Posted July 9, 2006 Actually, I'm running without a pullup resistor to the HEI module, but I still need one on the tach line. Mine absolutely wouldn't spark if I had a pullup on the HEI module. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted July 10, 2006 Share Posted July 10, 2006 the diagram looks like i am taking a 12v from the battery, running a 1k resister, then t connecting it to the megasquirt trigger line, Yes, that is correct Quote Link to comment Share on other sites More sharing options...
Forrest Posted July 10, 2006 Share Posted July 10, 2006 Ya I had trouble with the HEI too... I eventually gave up and went to a MSD. And i am much happier. I hate to say it but I utterly failed with the HEI as well - I bought 2 different HEI's, brand new, wired them exactly as instructed, couldnt' get any spark. I know tons of people use the HEI, so I don't know what I was doing wrong, but it just would not work. I hooked the MSD up and had the car running in 2 minutes. Quote Link to comment Share on other sites More sharing options...
mobythevan Posted July 10, 2006 Share Posted July 10, 2006 The HEI does require the bolts thru the module to be grounded or it won't work. Quote Link to comment Share on other sites More sharing options...
jimbo5670 Posted July 10, 2006 Author Share Posted July 10, 2006 ok, i had it grounded at the bottom, so i should run those 1k resisters inline with the tach and fidle wires, correct? or are they T connected with a 12v? Quote Link to comment Share on other sites More sharing options...
mobythevan Posted July 10, 2006 Share Posted July 10, 2006 They are T'd into the wires, NOT inline Quote Link to comment Share on other sites More sharing options...
jimbo5670 Posted July 18, 2006 Author Share Posted July 18, 2006 i still can't get any spark, and i have no idea why, ive ran though the connections a dozen times and cant find anything. megatuneSS is showing signal, but im getting nothing Quote Link to comment Share on other sites More sharing options...
mario_82_ZXT Posted July 18, 2006 Share Posted July 18, 2006 When I wired my HEI wiring wrong, I fried a diode and a transistor on the board. Go back to basics and run through the MS board tests, as well as the gate test on the HEI module. The parts were like $3 at radioshack to fix it. Mario Quote Link to comment Share on other sites More sharing options...
jimbo5670 Posted July 22, 2006 Author Share Posted July 22, 2006 alright, before i start to get frustrated and really screw things up, anyone in the south jersey area willing to give a bit of there time to help, 100 bucks if you can get it to fire. i just cant figure out what the problem is, and i just want to get this project moving again. thanks, matt Quote Link to comment Share on other sites More sharing options...
jimbo5670 Posted July 24, 2006 Author Share Posted July 24, 2006 alright, ive decided to have another crack at it, and was wondering what about the stock ignitor on the coil,is there any way i can use that eather in conjection with the HEI or independently using something else? Quote Link to comment Share on other sites More sharing options...
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