C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Bad ignition module symptoms

Thread Tools
 
Search this Thread
 
Old 09-26-2008, 11:03 AM
  #41  
rick lambert
Le Mans Master
 
rick lambert's Avatar
 
Member Since: Oct 2003
Location: seattle WA
Posts: 6,130
Likes: 0
Received 1 Like on 1 Post

Default

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.
rick lambert is offline  
Old 09-26-2008, 05:32 PM
  #42  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

Originally Posted by rick lambert
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.
....i never did check 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?
Da Mail Man is offline  
Old 09-26-2008, 06:06 PM
  #43  
rick lambert
Le Mans Master
 
rick lambert's Avatar
 
Member Since: Oct 2003
Location: seattle WA
Posts: 6,130
Likes: 0
Received 1 Like on 1 Post

Default

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?
rick lambert is offline  
Old 09-26-2008, 06:12 PM
  #44  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

...error deleted

Last edited by Da Mail Man; 09-26-2008 at 06:16 PM.
Da Mail Man is offline  
Old 09-26-2008, 06:14 PM
  #45  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

error..deleted...

Last edited by Da Mail Man; 09-26-2008 at 06:16 PM.
Da Mail Man is offline  
Old 09-26-2008, 06:20 PM
  #46  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

**let me see if i can get this post right!

Originally Posted by rick lambert
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?
**************************************** *
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...
Da Mail Man is offline  
Old 09-26-2008, 06:47 PM
  #47  
rick lambert
Le Mans Master
 
rick lambert's Avatar
 
Member Since: Oct 2003
Location: seattle WA
Posts: 6,130
Likes: 0
Received 1 Like on 1 Post

Default

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.
rick lambert is offline  
Old 09-26-2008, 06:53 PM
  #48  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

Originally Posted by rick lambert
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.
...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!!
Da Mail Man is offline  
Old 09-26-2008, 08:49 PM
  #49  
rick lambert
Le Mans Master
 
rick lambert's Avatar
 
Member Since: Oct 2003
Location: seattle WA
Posts: 6,130
Likes: 0
Received 1 Like on 1 Post

Default

BTW, after you get it out make sure you ohm each wire on the pigtail and clean the connections good.
Good Luck.
rick lambert is offline  
Old 09-27-2008, 01:10 PM
  #50  
SunCr
Le Mans Master
 
SunCr's Avatar
 
Member Since: Dec 2000
Location: San Diego, Ca
Posts: 7,839
Likes: 0
Received 19 Likes on 17 Posts

Default

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.
SunCr is offline  
Old 09-27-2008, 09:21 PM
  #51  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

Originally Posted by SunCr
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.
...i am aware of that...i usually try not to use the stuff packaged with the modules and have long since purchased and have been all along using the correct compound..it turns out that it seems all the modules i brought back for refund under life warranty have been good and now with the above info posted the other day (200 amp jump start info), seems like there may very well be a bad connection behind and down past the distributor which i will check asap and report back......
Da Mail Man is offline  
Old 09-28-2008, 04:58 PM
  #52  
67vetteal
Melting Slicks
 
67vetteal's Avatar
 
Member Since: Aug 2004
Location: Riverhead New York
Posts: 3,074
Received 99 Likes on 39 Posts

Default

Originally Posted by SunCr
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.
Are you saying that Thermal Grease is available at Radio Shack? Thanks, Al W.
67vetteal is offline  
Old 10-10-2008, 10:55 AM
  #53  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

Originally Posted by rick lambert
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; 10-10-2008 at 10:58 AM.
Da Mail Man is offline  
Old 10-10-2008, 11:16 AM
  #54  
onedef92
Team Owner
 
onedef92's Avatar
 
Member Since: Oct 2000
Location: Fort Knox, KY
Posts: 96,443
Likes: 0
Received 8 Likes on 8 Posts
Cruise-In IV Veteran
Cruise-In VI Veteran
Cruise-In VII Veteran
Cruise-In VIII Veteran

Default

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.
onedef92 is offline  
Old 10-10-2008, 11:19 AM
  #55  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

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.....
Da Mail Man is offline  
Old 10-10-2008, 12:08 PM
  #56  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

UPDATE;

...cleaned all contacts or bent same...sanded ground on distributor as well as gnd. lug....started right up......will monitor.....
Da Mail Man is offline  
Old 10-13-2008, 07:01 PM
  #57  
Da Mail Man
Safety Car
 
Da Mail Man's Avatar
 
Member Since: Jul 2004
Posts: 3,680
Received 22 Likes on 21 Posts

Default

......so far so good........
Da Mail Man is offline  
Old 11-06-2010, 11:14 AM
  #58  
coupeguy2001
Le Mans Master
 
coupeguy2001's Avatar
 
Member Since: Sep 2006
Location: Phoenix AZ
Posts: 6,043
Received 144 Likes on 106 Posts
2021 C4 of the Year - Modified Finalist

Default

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.
coupeguy2001 is offline  
Old 11-06-2010, 08:34 PM
  #59  
oldalaskaman
Le Mans Master
 
oldalaskaman's Avatar
 
Member Since: Aug 2010
Posts: 9,272
Likes: 0
Received 16 Likes on 12 Posts

Default

check dist. terminal board?
oldalaskaman is offline  



Quick Reply: Bad ignition module symptoms



All times are GMT -4. The time now is 06:08 AM.