chris_stampe

Ive tested everything I can think of and all that could be bad was the leading coil. There is no spark on the leading 2 plugs. I have gone through two other coil/ignitor packs and none worked. So Im wondering if the signal from the ecu could be wrong. there is a 12dcv signal to what I would guess is the power wire, and there is some sort of wavering signal to the other wire which i figured tells the coil/ignitor when to spark. But how can i tell if this signal is wrong? I know its not the spark plug wires, plugs, and im almost sure its not the coil/ignitor. Is there anything else i can check? THanks
btw does anyone know what kind of a signal should be goin to the coil besides the 12 volt dc on the i believe its a green wire?

HAILERS

That small white plug going to the LEAD COIL ASSY, has two wires. One black/yellow should have approx 12v. The other should have approx 5v that comes and goes as the engine is turned. Oh, and the two plug wires from this LEAD coil assy go to the two BOTTOM plugs on the engine. Does your car start at all????? A rx should be able to run with just the top two plugs(trail plugs) being fired. That coil assy is the one near the brake master cylinder.

chris_stampe

yes 12v and 5v. Sorry i had the colors messed up. No the car wont start. and yeah ive got the right coil to the right plugs and stuff.
I was reading my manuals just a bit ago and I am confused about something. Is the cpu the same as the ecu??? and also does the coil even get its signal of when to fire from the ecu or does it come directly from the cas or something else?? Thanks for your help, tomorrow i will try the atf trick and see what happens, cuz your right it should at least start up with 2 plugs.

HAILERS

The ECU is under the passengers feet. Pull rug up and find it under the steel plate there. The CPU does nothing for starting a car. Useless. The cas tells the ECU where the rotors are and the ECU fires the coils. I'd put one lead wire next to a stud next to the l/h strut tower and rotate the engine and look for spark. Sometimes a timing lite will not show the spark due to blah, blah, blah. Damn thing should spark. Spark damn thing! Do the trails spark??? Helps of course to have both sparking.

chris_stampe

Yes the trailing sparks, and I already tried to look for the spark after holding the wire up to ground. Also with the timing light, no spark on either of the leading wires. Do you guys think i should just buy a used ecu off of ebay for $30? How likely is it that that is the problem?

HAILERS

DArn again. Seems to me if you have the 12v and the 5v trigger signal the thing shoulda sparked. Is the coil assy attached to the frame good? With its four attach bolts? The coil assy has to be grounded for the coils to fire. Now I admit thats a reach, but its all I can think of if you tried several other coil assy's. Heck. AsK Keith(IRV).

HAILERS

Do you have a volt/ohm meter? And can you read the electrical schematics? I'm suggesting ringing out the cas at the ECU. If you are able to do this, I will make a effort to JPG the schematics tonite.

chris_stampe

Its actually only attatched by 2 bolts, but i ran some ground wires from it thinkin the same thing, but that didnt seem to help. Also it has had 2 nasty backfires when i was trying to start it. Dont think this would help but ya never know.

chris_stampe

Well my dad knows electronics so he could read them. But what do you mean by ringing out the crank angle sensor? Just testing the ohms? because i did that (not at the ecu, just at the 4 prong connector right next to it) and it checked out. Ive got the factory workshop manual and the haynes so I probably already have the diagrams. And yeah i have a volt/ohm meter. It would help if you told me what to test for though. Thanks

chris_stampe

hold on though if the ecu isnt gettin the correct signal from the cas, then the trailing coil shouldnt be firing right? if the trailing is working but the leading isnt, it cant be the cas because then both wouldnt work. correct me if im wrong

HAILERS

Some diagrams, three to follow.

HAILERS

Second:

HAILERS

Three:

HAILERS

Four:

HAILERS

Five and the last. By the way. Thirty bucks sounds good for a ECU. You could pull the largest plug off, the one with the most pins, and ohm b/t pins N and P. Then pins T and Q on the harness. I forget and am too lazy to look up the values right now, but they should ring out or ohm out. That means at least the wiring b/t the ECU and the cas is good. Really odd that coil *** isn't sparking though.

HAILERS

Now here's the deal. A fellow who goes by the online name of KEITH, who is really IRV, says that this car is peculiar in that on the lead coil assy, neither plug will fire unless the other is connected to its spark plug or is grounded. So when checking for spark on one of the leading plugs, make sure the other wire is on a plug or is grounded, please. So is that does not work do the ohm job with pins N to P and then T to Q. Forget about the jpg's since you have the manual with the same pages. Gotta go watch the tv now. There's a girl with no clothes on right now.

chris_stampe

YES!!! i have spark now
but still no start, oily gas on the plugs so im gonna try the atf trick. then i think i need to adjust my timing. thanks i dont really know what i did, maybe just wiggleing connections. i dont know

HAILERS

I'd go against the grain and make a fuel cut switch instead. Your flooded. See this thread https://www.rx7club.com/forum/showth...threadid=67963 and see if there is enough info for you to make one. If not I'll see if I can find a site with detailed instructions. Once unflooded an up and running you can check the compression and get an idea of where you are. Messing with the connectors must have reseated a connector. Congratulations. Special congrats for owning a factory service manual.