Bad ignition module symptoms
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
We may have covered this, but the pigtail (3-4 wires) coming out of the distributor, 6-8 inches long and very hard to see the next connection (behind engine) did you happen to check it? Hope I made that clear. At one time I happened to get careless (OK, more than once) When I clamped down the dizzy I accidentally clamped that pigtail underneath it. Crimped it...shorted it. Not saying you did that, but it's a section of wireing and connections I'd look at.
Safety Car
Joined: Jul 2004
Posts: 3,835
Likes: 30
We may have covered this, but the pigtail (3-4 wires) coming out of the distributor, 6-8 inches long and very hard to see the next connection (behind engine) did you happen to check it? Hope I made that clear. At one time I happened to get careless (OK, more than once) When I clamped down the dizzy I accidentally clamped that pigtail underneath it. Crimped it...shorted it. Not saying you did that, but it's a section of wireing and connections I'd look at.
the "other" connection behind the engine but, do know that it is almost impossible to see or get at!
..should i remove he distributor to get at it?
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
I think I just pulled the cap. It is a mother, short piece.When I went to the dealer they sold me one from a caddy, at stealership price...$98.
You may fabricate a hook out of a coat hanger to try fishing it out, but be gentle.
Question for you, not related to this. But didn't you have a fuel pump issue, where it would prime, but didn't have enough volumn, or something like that?
You may fabricate a hook out of a coat hanger to try fishing it out, but be gentle.
Question for you, not related to this. But didn't you have a fuel pump issue, where it would prime, but didn't have enough volumn, or something like that?
Safety Car
Joined: Jul 2004
Posts: 3,835
Likes: 30
**let me see if i can get this post right!
**************************************** *
I think I just pulled the cap. It is a mother, short piece.When I went to the dealer they sold me one from a caddy, at stealership price...$98.
***ouch!....is there another connector back there i should be looking at/for?
You may fabricate a hook out of a coat hanger to try fishing it out, but be gentle.
***see above
Question for you, not related to this. But didn't you have a fuel pump issue, where it would prime, but didn't have enough volumn, or something like that?
***yes, that was a long time ago..it would prime but, would not give me the pressure required. i replaced the fuel pump and all is well..each time the car would not start (as being discussed) i usualy take a fuel pressure gauge and check pressure as a matter of s.o.p. .however, is not the cae in all the non-starts i have been getting...
I think I just pulled the cap. It is a mother, short piece.When I went to the dealer they sold me one from a caddy, at stealership price...$98.
You may fabricate a hook out of a coat hanger to try fishing it out, but be gentle.
Question for you, not related to this. But didn't you have a fuel pump issue, where it would prime, but didn't have enough volumn, or something like that?
You may fabricate a hook out of a coat hanger to try fishing it out, but be gentle.
Question for you, not related to this. But didn't you have a fuel pump issue, where it would prime, but didn't have enough volumn, or something like that?
I think I just pulled the cap. It is a mother, short piece.When I went to the dealer they sold me one from a caddy, at stealership price...$98.
***ouch!....is there another connector back there i should be looking at/for?
You may fabricate a hook out of a coat hanger to try fishing it out, but be gentle.
***see above
Question for you, not related to this. But didn't you have a fuel pump issue, where it would prime, but didn't have enough volumn, or something like that?
***yes, that was a long time ago..it would prime but, would not give me the pressure required. i replaced the fuel pump and all is well..each time the car would not start (as being discussed) i usualy take a fuel pressure gauge and check pressure as a matter of s.o.p. .however, is not the cae in all the non-starts i have been getting...
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
No, if you feel comfortable pulling the dist. go for it. then you'll be able to pull the pigtail up. Like I said it's a short piece 4-6 inches long, then plugs into another connection. I think it's important you at least check it for bad connections.
Safety Car
Joined: Jul 2004
Posts: 3,835
Likes: 30
...no sweat on pulling the distributor as i had to do it to change the p/u coil...will give it a try and report back asap!...THANKS!!
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Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
For what it's worth, there's an article in November's Car Craft about HEI's, including basic troubleshooting and (at least unknown to me) that using dielectric - instead of thermal grease - will kill the Module. They found that some Auto Parts stores were passing off dielectric as thermal grease and got what was required at Radio Shack.
Safety Car
Joined: Jul 2004
Posts: 3,835
Likes: 30
For what it's worth, there's an article in November's Car Craft about HEI's, including basic troubleshooting and (at least unknown to me) that using dielectric - instead of thermal grease - will kill the Module. They found that some Auto Parts stores were passing off dielectric as thermal grease and got what was required at Radio Shack.
Melting Slicks
Joined: Aug 2004
Posts: 3,078
Likes: 101
From: Riverhead New York
For what it's worth, there's an article in November's Car Craft about HEI's, including basic troubleshooting and (at least unknown to me) that using dielectric - instead of thermal grease - will kill the Module. They found that some Auto Parts stores were passing off dielectric as thermal grease and got what was required at Radio Shack.
Safety Car
Joined: Jul 2004
Posts: 3,835
Likes: 30
We may have covered this, but the pigtail (3-4 wires) coming out of the distributor, 6-8 inches long and very hard to see the next connection (behind engine) did you happen to check it? Hope I made that clear. At one time I happened to get careless (OK, more than once) When I clamped down the dizzy I accidentally clamped that pigtail underneath it. Crimped it...shorted it. Not saying you did that, but it's a section of wireing and connections I'd look at.
...ok, another "no start day" today!...so;
1...removed cap and wires
2...removed rotor
3...removed pigtail from distributor that connects directly to
ignition module (one wire to distributor case is ground) and left
other end connected to harness.
4...the wires are colored as follows (colors may be faded due to
age);
A) purple w/white tracer
B) orange w/black tracer
C) yellow
D) black w/red tracer TO DISTRIBUTOR CASE GROUND
MEASURED VOLTAGES WITH IGNITION ON;
YELLOW + PURPLE W/WHITE TRACER............................= 0.16V
YELLOW + ORANGE W/BLACK TRACER...........................= 0.00V
PURPLE W/WHITE TRACER + ORANGE W/BLACK TRACER....= 0.04V
ORANGE W/BLACK TRACER + BLACK W/RED TRACER (GRND)= 0.00V
YELLOW + BLACK W/RED TRACER =.................................0.20V
**************************************** ******
while i have not pulled apart the concealed connector as of yet, should there not be AT LEAST 12vdc on any one of these connections powering up the ignition module? also, could or is there an ignition fuse that guards the system? (maybe loose or bad connection at fuse). my manuals are not with me at this time...opinions?...THANKS!
Last edited by Da Mail Man; Oct 10, 2008 at 10:58 AM.
Team Owner
Joined: Oct 2000
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From: Fort Knox, KY
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Mine made the engine miss lightly when warmed up. One day, it died suddenly, taking my coil out with it.
Engine just quit, resulting in a crank, no-start condition.
Engine just quit, resulting in a crank, no-start condition.
Safety Car
Joined: Jul 2004
Posts: 3,835
Likes: 30
coil good..had new one in and went back to old one....same results...cki'ng voltages at connector with pigtail disconected now....suspect a dirty ground on wire as above to case.....however, that doesn't explain why no voltages at pigtail that connects to ignition module.....
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
Stealth, I would put a capacitor on the power wire on the 3 wire plug that goes to the module in the distributor.
It sounds like you have a voltage spike occasionally when either shutting off the car or turning on the ignition switch, and over time, it finally burns out the power transistor inside the module.
It sounds like you have a voltage spike occasionally when either shutting off the car or turning on the ignition switch, and over time, it finally burns out the power transistor inside the module.
