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Electronic ignition module meltdown ?

  • Thread starter Thread starter mustang2
  • Start date Start date Sep 30, 2004
M

mustang2

New Member
Apr 29, 2004
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NC
Sep 30, 2004
#1
  • Sep 30, 2004
  • #1
This was like this when we bought the car, so I don't know how or when this happened, we are just now getting to it in the restoration. The car does still start and run.
The coating on the back of the module is melted.
What would cause something like this to happen? Whatever caused this I will need to fix it. Anybody have any idea what would cause this?
Also anybody have any ideas on how to remove this from the engine bay? It's very gooey, I tried a putty knife, that don't work.

 
D

dmoody

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Nov 4, 2002
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Winston-Salem, NC
Sep 30, 2004
#2
  • Sep 30, 2004
  • #2
Paint stripper would probably be your best bet. However I think a hot water pressure washer would work as well.

d
 
J

jshcobra

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Sep 30, 2004
#3
  • Sep 30, 2004
  • #3
Someone probably left the key in the "on" position with the motor not running. I had that happen on a 79 Mustang but it was the wiring harness that burned. In this case, the wires proved stronger than the module.
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
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NE Ohio
Sep 30, 2004
#4
  • Sep 30, 2004
  • #4
Damn!

Is this a factory module?

I've seen several failed modules. The power transistor usually heats the resin to charring, discoloring or splitting, Never seen one melt.
 
M

mustang2

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Apr 29, 2004
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#5
  • Sep 30, 2004
  • #5
Wart said:
Is this a factory module?
Click to expand...
It's a Motorcraft module. I have never seen anything like this before either.

jshcobra: That sounds like a pretty good assumption. I hope that's all it was anyway.
 
7

77sleeper

GO BUCS!
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#6
  • Sep 30, 2004
  • #6
I had one do that as well, KOEO will do that, also heard rumor that the unit is a case ground. mine has not done that since I ran a case to chassis bond
 
M

mustang2

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#7
  • Sep 30, 2004
  • #7
77sleeper said:
I had one do that as well, KOEO will do that, also heard rumor that the unit is a case ground. mine has not done that since I ran a case to chassis bond
Click to expand...
What is a KOEO?
 
Z

zwhitr

Founding Member
Aug 26, 2001
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Goldsboro, NC
Sep 30, 2004
#8
  • Sep 30, 2004
  • #8
I had one like that the resin was very goey but didnt leak all over like that but I replaced it on site

now I am runnin the MSD 6AL

with another duraspark mod on back up
 

dastang2

Active Member
Dec 11, 2003
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tx
Oct 1, 2004
#9
  • Oct 1, 2004
  • #9
i have seen that as well on a 77 flatbed truck with a 460, they get old and stuff happens
 
C

cobraii74x

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Aug 27, 2003
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Oct 1, 2004
#10
  • Oct 1, 2004
  • #10
KOEO... maybe it means key on.. engine off.. I dunno.. but there was the remnance of that in my friends turbo coupe as well
 
7

77sleeper

GO BUCS!
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Napalm, AZ
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#11
  • Oct 1, 2004
  • #11
cobraii74x said:
KOEO... maybe it means key on.. engine off.
Click to expand...

yup sorry
 

COBRA 7

Founding Member
May 19, 2000
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Oct 7, 2004
#12
  • Oct 7, 2004
  • #12
The control mod. starts the car with 12 v and it runs on 9 v.

Maybe the resistor wire under the dash had failed and someone rewired it to run all the time on 12 v.
 

1970impala

Please God, somebody find me some WHITE CARGO PANE
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Jan 22, 2002
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Pennsylvania
Oct 8, 2004
#13
  • Oct 8, 2004
  • #13
Damn, never seen that happen before!!! I have the original on my car and really don't trust it being so old so i bought another and stuck it in the toolbox that i take to shows with me just in case. You never know.
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
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58
NE Ohio
Oct 8, 2004
#14
  • Oct 8, 2004
  • #14
COBRA 7 said:
The control mod. starts the car with 12 v and it runs on 9 v.

Maybe the resistor wire under the dash had failed and someone rewired it to run all the time on 12 v.
Click to expand...



A real possability.
 
M

mustang2

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Apr 29, 2004
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Oct 9, 2004
#15
  • Oct 9, 2004
  • #15
COBRA 7 said:
The control mod. starts the car with 12 v and it runs on 9 v.

Maybe the resistor wire under the dash had failed and someone rewired it to run all the time on 12 v.
Click to expand...
Tell me more about this. Where is the resistor wire located under the dash? Where am I looking at if it might have been rewired. Where's the control modulator?
I'm sorry but I stink when it comes to electrical.
I appreciate any help.

On a side note, I checked all the wiring on the drivers side engine compartment and everything looks to be in good shape.
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
3
58
NE Ohio
Oct 9, 2004
#16
  • Oct 9, 2004
  • #16
mustang2 said:
Tell me more about this. Where is the resistor wire located under the dash?
Click to expand...


Good question. It would have to be in the loome between the switch and coil. All the coil power wires I've seen in IIs have been green with yellow stripe, start there and work back.


Where am I looking at if it might have been rewired.
Click to expand...

Between the switch and coil.

Easy way is to measure the voltage at the coil. It should read 7 to 8.5 volts (+-) depending on year. Everything ignition must be plugged in.


On a side note, I checked all the wiring on the drivers side engine compartment and everything looks to be in good shape.
Click to expand...

Funny things happen inside harnesses, I started taking one apart and found several wires had grown together.
 
M

mustang2

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Apr 29, 2004
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Oct 10, 2004
#17
  • Oct 10, 2004
  • #17
Thanks Wart, I'll start looking into it.
 

Wart

I'm Mad as HELL and I'M not Gonna Take it ANYMORE!
Founding Member
Sep 1, 1998
408
3
58
NE Ohio
Oct 10, 2004
#18
  • Oct 10, 2004
  • #18
I got back into a manual ... gotta love manuals.

1 - 2 ohms for 73 to 76.
0.7 - 1.7 ohms for DuraSpark II through 77
1.05 - 1.15 for 78 and later.

DuraSpark 1 doesn't use a resistor wire.

DS1 also shuts down coil current if the modulator senses the engine isn't running. Easily explains how a II box in a 1 car could cause a module melt down if KOEO.

DS1 was used in Cali cars, but not all of them.

Working on the ignition isn't too difficult, once you know exactly which system your working on.
 
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