Author Topic: Yet MORE coil problems...  (Read 11546 times)

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Offline jfrabat

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Re: Yet MORE coil problems...
« Reply #45 on: April 01, 2012, 04:27:24 PM »
i wonder if this is why your PCM got fried a while back (if it did, i seem to recall you said something to that nature in one of your threads).

No, that was a friend, not me.  I did buy a used ecu when that happened to him to keep as a spare, but mine is still alive and kicking.
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline jfrabat

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'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline grumpygy

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Re: Yet MORE coil problems...
« Reply #47 on: April 01, 2012, 05:49:35 PM »
Glad I could help.
94 YJ, Cool Air intake, 19lb Inj, 4.0 Throttlebody with spacer,  31/10.50/15's

Offline jfrabat

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Re: Yet MORE coil problems...
« Reply #48 on: May 06, 2012, 10:16:31 PM »
So, I put in a new Mopar coil, the new connector, checked everything, and they coil started acting up again (I swaped it out before I burned it).  Do I now install the Mallory 0.7-1.5 Ohm ballast resistor?  I am also considering installing a new mounting bracket to the frame to get the coil  away from the enginr's heat (in case that's what's causing the problem...  Any other ideas are welcome!
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline sharpxmen

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Re: Yet MORE coil problems...
« Reply #49 on: May 06, 2012, 11:04:01 PM »
swap the PCM and see if it does it again (you have a spare right?)
'95 YJ, NSG370 6spd / Hurst shifter, Dana 300 + 4:1 Doubler / tri-stick, Custom skid, Super D35 / Auburn LSD / 4.88, 35x12.5x15 BFG KM2, 64mm t/b, 1.7 RollerRockers, MkVIII e-fan, Dual Diaph Booster
Latest: Corbeau BajaRS heated seats :dance: keeping warm the rear end

Offline jfrabat

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Re: Yet MORE coil problems...
« Reply #50 on: May 06, 2012, 11:40:07 PM »
swap the PCM and see if it does it again (you have a spare right?)

I did that when I put in the coil that started acting up...
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline sharpxmen

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Re: Yet MORE coil problems...
« Reply #51 on: May 06, 2012, 11:43:12 PM »
i've never seen this happening before with all the things you swapped already so i'm out of ideas.
'95 YJ, NSG370 6spd / Hurst shifter, Dana 300 + 4:1 Doubler / tri-stick, Custom skid, Super D35 / Auburn LSD / 4.88, 35x12.5x15 BFG KM2, 64mm t/b, 1.7 RollerRockers, MkVIII e-fan, Dual Diaph Booster
Latest: Corbeau BajaRS heated seats :dance: keeping warm the rear end

Offline jfrabat

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Re: Yet MORE coil problems...
« Reply #52 on: May 06, 2012, 11:49:49 PM »
i've never seen this happening before with all the things you swapped already so i'm out of ideas.

I think I will install the extra coil bracket (it would make cvhanging coils on my way to Panama) and include the. Ballast resistor there.  I will order a coil extension chord, and have it ready to plug into the resistor if that coil fails.  I just need to figure out how to make the holes the the frame, as I just found out my drill will not fit in there...
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline grumpygy

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Re: Yet MORE coil problems...
« Reply #53 on: May 07, 2012, 09:24:00 AM »
Ok just read everything again and did not see this.  Have you changed the coil Wire.  Had one on my truck(One coil per Cylinder) and started frying coils.  It ended up being the coil wire had a internal break.  This would act just like you had a too large of plug gap and overheat the coil.


  Just a shot in the dark.
94 YJ, Cool Air intake, 19lb Inj, 4.0 Throttlebody with spacer,  31/10.50/15's

Offline jfrabat

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Re: Yet MORE coil problems...
« Reply #54 on: May 07, 2012, 08:48:56 PM »
Ok just read everything again and did not see this.  Have you changed the coil Wire.  Had one on my truck(One coil per Cylinder) and started frying coils.  It ended up being the coil wire had a internal break.  This would act just like you had a too large of plug gap and overheat the coil.


  Just a shot in the dark.

At this point, its worth a try, but I doubt this is the issue, as it has dones for a while now.  How about a bad grou d?  Vould that be the cause?  How would I check for this?
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline grumpygy

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Re: Yet MORE coil problems...
« Reply #55 on: May 07, 2012, 08:57:01 PM »
Pull the wire check for resistance.  While doing it move the wire around.  Mine showed a a break.
94 YJ, Cool Air intake, 19lb Inj, 4.0 Throttlebody with spacer,  31/10.50/15's

Offline jfrabat

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Re: Yet MORE coil problems...
« Reply #56 on: May 08, 2012, 09:02:29 PM »
Anyone knows where I can get an extension of the coil wire?  I want to modify one to use with the ballast resistor (so it will be easy to plug it in or bypass it), but I cannot find one online...
'94 YJ 2.5L with 4" RE lift, Superwinch EPi9.0, FoMoCo e-Fan, SD30 and SD35 w/ARB-5.13, 165A alt., 33" BFG KM2 on 15" AR wheels, Sony sound system, Pavement Ends Hardtop, Hydroboost

Offline grumpygy

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Re: Yet MORE coil problems...
« Reply #57 on: May 08, 2012, 11:07:06 PM »
If you have not changed the Distributor and are using a stock coil, there is something else wrong.
94 YJ, Cool Air intake, 19lb Inj, 4.0 Throttlebody with spacer,  31/10.50/15's

Offline Jeffy

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Re: Yet MORE coil problems...
« Reply #58 on: May 09, 2012, 03:13:32 PM »
I still think there is an issue with the stock wiring.  There's too much resistance in that wire which is causing it to overheat and melt the plug/coil.
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Offline grumpygy

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Re: Yet MORE coil problems...
« Reply #59 on: May 09, 2012, 03:25:11 PM »
Wonder if somehere before the wires were reversed to the coil. 

Here is a way to check.

http://mgaguru.com/mgtech/ignition/ig104.htm
94 YJ, Cool Air intake, 19lb Inj, 4.0 Throttlebody with spacer,  31/10.50/15's