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WTF???? my lead coil isn't firing

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Old Apr 17, 2003 | 07:33 PM
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Rotary Freak
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WTF???? my lead coil isn't firing

well, my engine ran!!!!! and its still running!!!!!!

but its only running on the trailing coil???

I didn't think that was even possible.

well, anyway, I guess I'm going to go and change my leading coil(unless its good), and hopefully it will work good, and start up good and everything.

I don't know why I didn't catch that earlier. 2 damn weeks.

YES!!!!!!!!!!!!!!
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Old Apr 17, 2003 | 09:32 PM
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wow, for like the last hour, I've been trying to open up this site, but ti wouldn't open. anyway, I replaced teh coil, still nothing.

I tested the power going to the coil, and I guess teh ground isn't good enough. I pulled open the plug, and put the + side of the voltmeter on the black wire, and the - side on the green wire, and it showed around 9 volts. when I touched a different ground than the green wire, it showed just above 12 volts. so now I'm thinking the ground before the coil isn't good enough(if that makes any sense), and that I need to add another ground. I'm kind of confused about this. the coil works fine, but its not creating a spark.

does anyone have any idea why a good coil wouldn't be sparking(it has power)? I'm kind of confused about this, so any input would be great.
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Old Apr 17, 2003 | 09:35 PM
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that's right, feel the superior power of N/A!!! What's this? My car STARTS!
Did you try adding or improving the ground yet?
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Old Apr 17, 2003 | 09:42 PM
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I don't know how I could do that.

could I just splice in another wire to the green one? or what?
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Old Apr 17, 2003 | 09:56 PM
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what if you splice the green wire straight to the chassis? The only thing I'd worry about is possible extra electrical interference.
You could try it temporarily by stripping a piece of the insulation off and running clips from that spot straight to the chassis.
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Old Apr 17, 2003 | 10:10 PM
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maybe I'll try just jamming a peice of wire into the plug, and then trying to connect the plug.

or I could do it your way
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Old Apr 17, 2003 | 10:12 PM
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Sounds to me like your well on your way to shorting out your ECU and or ignitor. Oh well.

The Black/Yellow should have 12v on it. The Green/Yellow is the trigger wire. It should have 5v coming and a going. You don't wanna ground that wire, please.

http://www.teamfc3s.org/info/articles/demystifying.html

Last edited by HAILERS; Apr 17, 2003 at 10:34 PM.
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Old Apr 17, 2003 | 10:22 PM
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I just went out and started my car on only the trailings; I can't believe it it started! Anyway, it idles at about 100 rpm (100, not 1000!), but will rev up fine and everything. I don't know though, on only the trailings it doesn't sound very healthy.
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Old Apr 17, 2003 | 10:35 PM
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rotary>piston.......Disconnect the trail coil assy and you can redline the darn thing and never notice the trail isn't there. Normal. Trail only makes the car sluggish. NO good.
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Old Apr 17, 2003 | 11:01 PM
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I disconnected the leadings, you know, the ones that matter? It was running on just the trailings, that's why I was surprised it ran.
Anyway, I was just seeing if my car ran similar to his to see if it might in fact be a lack of leading plug fire making his car run so badly.
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Old Apr 17, 2003 | 11:01 PM
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yes. thanks hailers. I was hoping someone who new something would help me out.

so you're saying if I put the + in the black, and - on the ground I should get 12V? well, I got that.

and if I put the + in the green, and - on the ground I should get 5V? haven't tried that. what if I don't?

and if I do, why aren't I getting any spark?

oh yeah, and is there supposed to be any resistance between the two places where the plug wires plug in to the lead coil?

oh yeah, and I'm not sure if this helps in this situation, but I've added 2 extra grounds to the battery. one from - to chassis, and one from + to engine...... hahahahaha NO! 2nd one from - to engine(the alt mounting bracket thing). now my starter acutally works. I even disconnected the stock main ground on the starter mount, and it didn't seem to do anything. could this ground be bad and somehow effect the leading coil? even with the other 2 connected, and working properly?

also, I haven't yet done those wiring things I need to do to make my TII swap be "done right", like the knock sensor wire and stuff. could that somehow effect the leading coil?

thanks
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Old Apr 17, 2003 | 11:04 PM
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god I wish we'd started the engine before doing the swap
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Old Apr 17, 2003 | 11:06 PM
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oh yeah travis, if you want confusing wiring diagrams, I've got about a million of them in my manual.
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Old Apr 18, 2003 | 06:18 PM
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damn. the coil seems to be getting power, and working properly. but it still isn't creating any spark?

so I guess it must have something to do with the CAS or ECU, but the trailing coil still works, so what could be wrong?




if the timing was REALLY REALLY REALLY far off, would that make the leading coil not fire at all? while the trailing would still be firing? I'm confused.

what else could make just the leading coil not fire?

Anyway, I was just seeing if my car ran similar to his to see if it might in fact be a lack of leading plug fire making his car run so badly.
I pulled off both leading plugs from the coil(after the timing light didn't flash), and it made no difference. I'm 99% sure that's what's wrong.

Last edited by Bigretardhead; Apr 18, 2003 at 06:21 PM.
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Old Apr 18, 2003 | 07:53 PM
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First, the trailing plug is designed to burn any unused fuel not burned in the leading stroke (so to speak). So, since you're not getting spark on the lead and no fuel is being burned it's not suprising that it will run with the trailing igniting all of that fuel. Silly question but have you switched the plug wires? How about swapping the coils from leading to trailing.
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Old Apr 18, 2003 | 08:02 PM
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If you pulled the lead plug wires off and the car ran just the same as before it does seem the Lead coil assy is bad. Probably the Igniter inside it.

On the two wire plug at the lead coil assy...never ground either wire. The black with a yellow stripe should have 12v on it. The other wire, green/yellow......don't bother looking at it. It has 5v coming and a going when the engine turns over to trigger the ignitor. Comes from the ECU.

I'd go to the junk yard and get a 25 buck used one. Lead coil assy.

Never ever ground the green/yellow wire or the black/yellow.

Just put the positive lead of the meter on the black/yellow wire and the negative lead of the meter on either the battery ground or just some bare metal on the chasis or engine. Should see 12v with the key to ON.

Timing being off won't stop sparking of the lead coil assy.
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Old Apr 18, 2003 | 08:11 PM
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okay, well I already tried swapping the coil from one from my parts car. it didn't make a difference.


and I checked the power at the wires. its exactly what it should be, except teh green one had 6 rather than 5V.

hmmm.....
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Old Apr 18, 2003 | 11:04 PM
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hmm... this is really weird. If I unplug the trailing coiil, the leading coil works, and then I can plug in the trailing coil again. It won't start with both coils plugged in, it just makes a weird whining sound, and no turning over.

has anyone ever seen this happen before?
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Old Apr 18, 2003 | 11:08 PM
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Hey dude, email me at temperature21@yahoo.com...I'll help you fix your problem....I encounter the same problem you did....Turn out that the fuel cutoff switch I installed was open. Maybe you want to check under your steering colum for the five pin plug and make sure it's not disconnected.
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Old Apr 18, 2003 | 11:18 PM
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im having a similiar problem with mine except i have no spark from either of the coils?? but i do have 12 volts on the black/yellow and nothing on the green/yellow?? does anyone have advice
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Old Apr 18, 2003 | 11:25 PM
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CHeck your wires for a good resistance ~13-16ohms. Get new spark plugs. Lastly, check under your steering colum, between the colum and the radio, there should be a five plugs connector. It's yellow and connected to a black relay box. Make sure that is connected.
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Old Apr 19, 2003 | 12:10 AM
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okay, I'll make sure that is connected, but what is it?

but the car runs great now, it just won't start unless I unplug one of the coils(preferably trailing, sometimes trailing only doesn't start it so good). but the leading coil starts it great.

this just seemed kind of weird. its like there's a short to the starter when both are connected. it just makes a weird buzzing sound. whatever.


im having a similiar problem with mine except i have no spark from either of the coils?? but i do have 12 volts on the black/yellow and nothing on the green/yellow?? does anyone have advice
if you have nothing on the green/yellow wire, it probably means its not getting a signal from the CAS or ECU. also, when you test it, did you put + in black and - in green, or + in green and - on ground?
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Old Apr 19, 2003 | 12:12 AM
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ive checked the leading resistance and its 14 ohms but i dont get a reading from the trailing i have yet to check that box... what is it? also do you know how to check the cas or ecu?

Last edited by 87basemodel; Apr 19, 2003 at 12:16 AM.
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Old Apr 19, 2003 | 12:41 AM
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yeah, WTF is wrong with your car? This wiring **** sucks. Does it start now with both coils plugged in?
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Old Apr 19, 2003 | 12:58 AM
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don't know dude. haven't tried since you left like an hour ago. hehe.
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