2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

No Spark on Leading Coil

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Old 04-15-04 | 09:45 PM
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No Spark on Leading Coil

hey guys ive been working on my car for a while now and i moved it today and it just cut off. so i tried to restart it back up both nothing happend. i have fuel but no spark. there is no spark on the leading coil. there is a stead spark on the trailign coil but non on the leading. i tried switching the coils from the na and it didnt help at all. so i know the coil wasnt bad. i have power to the coil but no spark. could it be my ecu or CAS maybe?
Old 04-16-04 | 12:43 AM
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iit should be able to run even if L plugs dont fire. Or if T plugs dont fire, just as long as one of them makes a spark. Are the plugs fouled out? I'd start with all the basics. Do you have any air leaks? How do you know you have fuel and primary injectors are operating? Absolutely sure its not flooded?

you could try swapping the CAS from other car and setting timing.

your on the right track, just keep checking everything...
Old 04-16-04 | 12:49 AM
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From: FK EPIC FU
Whoa.

before all that crazy loco just check your 15A eng fuse.
Old 04-16-04 | 07:50 AM
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all the fuses are good, and the plugs are brand new. i dotn have another cas to swap into this car. i tested the fuel pump and its getting proper voltage. and i can feel fuel runing through the lines so i know i have fuel. i hva e a fuel cut switch so when i try to strat it i turn fuel off if its flooded but nothing happens whether the fuel cut switch is on or off. but it isnt startign off jsut the trailign plugs

please help
Old 04-16-04 | 02:57 PM
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Old 04-16-04 | 04:14 PM
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Put a scope on the input (from the ECU) lines to the coil...Do you see a square wave when someone cranks the car?
Old 04-16-04 | 11:24 PM
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I dont have a scope, is there anythign else i coud do?

also is the CAS from na and turbo cars the same?
Old 04-18-04 | 01:25 PM
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BUMP!

help guys my car wont even start. it should start even if no spark on leading coil. i haev spark on trailing? im gonna try to change the CAS with the one in my na and see if it helps. but if you guys have any more ideas PLEASE help me!!!
Old 04-18-04 | 01:50 PM
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Well maybe you should inspect the plug that's on the CAS....

A while back I was looking at a spare CAS I have and noticed that the female receptors we're kinda jacked up.
One was stuffed up out of place. Look at the male connector plug on engine harness too.

Also if all the electrical receptors are in good shape, maybe take a multimeter and test the resistences of the CAS as found in the FSM.

I did that yesterday, and would gladly post the link except the pdf isn't working right now. (?)
Old 04-18-04 | 04:38 PM
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i used a test light on the CAS plug and they they light up so i dont think it is the plug. but ill look in the FSM and test the resistance also.
Old 04-18-04 | 04:57 PM
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won't be too hard to check the coil resistances with a meter to rule that out...FSM provides procedures for troubleshooting the igniters/ coils starting on page 5-32...if you have an inductive timing light you can verify spark/ no spark on the plug wires...
Old 04-18-04 | 06:53 PM
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yes, the CAS from a N/A and TII are the same.
Old 04-18-04 | 09:59 PM
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anything else to check for tommrow?
Old 04-19-04 | 06:14 PM
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well thanks guys, you really helped. NOT

anyway it was the computer. i guess i soldered something wrong when installing the SAFC2. oen of the things in the computer is burnt up.

by the way does anyone have a N332 ecu for sale?
i posted a forsale add also
Old 04-22-04 | 07:51 PM
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GRRRRRR! this car is pissing me off so much. the ecu i bought didnt work. so it wasnt my ecu.

Ok so its not the coils, CAS becuase i changed it with the one in my na and still doesnt work, or the ECU.
what could be wrong, i was reading another thread and HAILERS said that if the tach bounces then i have spark. but if i hold the spark wire up to the coil so they almost touch i see no spark. but if i do it on the trailing coil i do see spark. what could be worng? could there be a wire in between the ECU to CAS or CAS to coils?

what should i check? PLEASE HELP !!
Old 04-22-04 | 08:01 PM
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did all your problems start when you "installed" the SAFC2? I don't agree with checking out ANYTHING that sends an input to the ECU with a test light for one thing, the smart-*** "well thanks guys, you really helped, NOT" statement compels me to ignore you now, since your problem is probably self-induced anyway...
Old 04-22-04 | 08:19 PM
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ok well wayne i checked my wiring for my safc and it is all correct according to 1300cc.com's write up. and im sorry about my comment i made sometimes i jsut get so pissed off because someone else moved ym car then it all a sudden doesnt run anymore. ive spent 3 months tring to get this car running and it is very stressful.

i just want to know whats f*cking wrong with my damn car.
Old 04-22-04 | 08:43 PM
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O.K., apology accepted, and I feel your pain (don't forget, I've got an rx-7 too!) Now, start from the top:what OEM wiring had to be disturbed for the SAFC2 install? obviously, if it ran fine before then it's probably something YOU did...there aren't a lot of components in the ignition system- 1)80A main fuse, 2)15A eng fuse, 3)main relay, 4)ECU triggering signal, 5) the coil/ igniter units, 6) capacitor circuit to ground (for noise), 7) plug wires & plugs, and 8) all the wiring that carries the "trons" (if the injectors are working, you can rule out 1-3)...oh yeh, and the CAS...now, what HAVEN'T you checked?
Old 04-22-04 | 09:09 PM
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for the safc you had to solider RPM signal, TPS, 2 grounds on the ecu, and 2 airflow/pressure signals.

but i was wondering if i am missing a ground form the body to block or somethign alongs those lines would that cause this?

and shouldnt my car start even if leading not having spark but trailing is creating spark? i know on my na it will start without the leading connect hooked up.( i left it off on accident while swaoing out coils from na - tII)
Old 04-22-04 | 09:35 PM
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what wire did you use for the RPM signal? are you sure you didn't ground it somehow? and the grounds on the ECU- were they existing grounds? and you never answered my question- did it run good BEFORE you started playing with it?
Old 04-22-04 | 09:44 PM
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well... i bought the car and it hesitated alittle at 5k so i took the car apart adn started modding it. All teh mods in my sig for teh turbo II. i ported the wastegate, cleaned out turbo put walbro and 720cc injectors, new 3 inch exhaust, re wrapped all wires(here is what i might have messed up) cleaned and painted all manifolds pretty much made everythign nice. i installed the safc before i got it running, which might have been a bad idea becuase i dont know if it was something i did before the safc install or when i installed the safc.

and the grounds for the ecu was a wire that connect to the ecu i dont know where it coems from. i just used the diagram from here http://www.1300cc.com/howto/how2/safc.htm
i went exactlly by this to install teh safc2
Old 04-22-04 | 09:55 PM
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so it could be one of 50 or so things, lol...only thing that pops in my head would be a bad solder joint- I use butt splices all the time- it's just a PITA to create a good solder joint on a cold wire...If butt/ crimp splices are good enough for the planes I work on, they're good enough for my car (gotta use the correct crimper tools, of course).
Old 04-22-04 | 11:34 PM
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****what could be wrong, i was reading another thread and HAILERS said that if the tach bounces then i have spark****

Well, I was half right on that statement. It means you have spark at the TRAIL plugs, not for sure on the LEADS.

But, that should rule out any thoughts about it being a fuse, main relay, and ECU grounds. Both coil assy use the same fuses for power and the ECU uses the same ground (2C).

If you use a meter AT the ECU, looking BACK TOWARDS THE CAS, and ring the four wires out thru the coils in the CAS....that should show whether the cas wiring is any good.

And you know the engine will run on just the Trails because you've seen that for yourself in the past on your n/a.

Part of me is tempted to tell you to swap your na ECU into your turbo and give it a try. They're both about the same year? One a 326..the other a 332? If those are th numbers I'd have a go at that. I've done that in the past on my na and turboii for starting purposes. I WOULD NOT DO THAT if your numbers are not those.

Beware of test lights. I don't own one and never have uses one...but I understand they might/can put too much of a load on some ECU components and fry them so to speak.

I've no idea why your LEAD coil is not firing since your Trail is. The only thoughts that come to mind are the ECU or the coil not being bolted to the frame with at least one bolt/fastener. The coil/ignitor is grounded thru the assy's body.
Old 04-22-04 | 11:36 PM
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****what could be wrong, i was reading another thread and HAILERS said that if the tach bounces then i have spark****

Well, I was half right on that statement. It means you have spark at the TRAIL plugs, not for sure on the LEADS.

But, that should rule out any thoughts about it being a fuse, main relay, and ECU grounds. Both coil assy use the same fuses for power and the ECU uses the same ground (2C).

If you use a meter AT the ECU, looking BACK TOWARDS THE CAS, and ring the four wires out thru the coils in the CAS....that should show whether the cas wiring is any good.

And you know the engine will run on just the Trails because you've seen that for yourself in the past on your n/a.

Part of me is tempted to tell you to swap your na ECU into your turbo and give it a try. They're both about the same year? One a 326..the other a 332? If those are th numbers I'd have a go at that. I've done that in the past on my na and turboii for starting purposes. I WOULD NOT DO THAT if your numbers are not those.

Beware of test lights. I don't own one and never have uses one...but I understand they might/can put too much of a load on some ECU components and fry them so to speak.

I've no idea why your LEAD coil is not firing since your Trail is. The only thoughts that come to mind are the ECU or the coil not being bolted to the frame with at least one bolt/fastener. The coil/ignitor is grounded thru the assy's body.
Old 04-22-04 | 11:38 PM
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****what could be wrong, i was reading another thread and HAILERS said that if the tach bounces then i have spark****

Well, I was half right on that statement. It means you have spark at the TRAIL plugs, not for sure on the LEADS.

But, that should rule out any thoughts about it being a fuse, main relay, and ECU grounds. Both coil assy use the same fuses for power and the ECU uses the same ground (2C).

If you use a meter AT the ECU, looking BACK TOWARDS THE CAS, and ring the four wires out thru the coils in the CAS....that should show whether the cas wiring is any good.

And you know the engine will run on just the Trails because you've seen that for yourself in the past on your n/a.

Part of me is tempted to tell you to swap your na ECU into your turbo and give it a try. They're both about the same year? One a 326..the other a 332? If those are th numbers I'd have a go at that. I've done that in the past on my na and turboii for starting purposes. I WOULD NOT DO THAT if your numbers are not those.

Beware of test lights. I don't own one and never have uses one...but I understand they might/can put too much of a load on some ECU components and fry them so to speak.

I've no idea why your LEAD coil is not firing since your Trail is. The only thoughts that come to mind are the ECU or the coil not being bolted to the frame with at least one bolt/fastener. The coil/ignitor is grounded thru the assy's body.



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