8 Ignition Modules later
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Post #18, you took the module to autozone and it tested good after 3 trys? To test the module correctly they need to run it through the cycle at least 10 times, if you're saying they ran it through 10 cycles 3 times OK, if not then it has to be ran through 10 cycles. The reason is, the modules are heat sensitive and it takes at least 10 cycles for it to get hot....it may test good when cold, or even start a car, but as it heats up if it's failing that's when they show there ugly head...engine dies, and won't start again until the module cools off.
Thread Starter
Safety Car
Joined: Jul 2004
Posts: 3,838
Likes: 30
Post #18, you took the module to autozone and it tested good after 3 trys? To test the module correctly they need to run it through the cycle at least 10 times, if you're saying they ran it through 10 cycles 3 times OK, if not then it has to be ran through 10 cycles. The reason is, the modules are heat sensitive and it takes at least 10 cycles for it to get hot....it may test good when cold, or even start a car, but as it heats up if it's failing that's when they show there ugly head...engine dies, and won't start again until the module cools off.
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
This really sounds wierd to me. OK, let me ask the question, how or what brought you to believe the ign. module was the culprit? I know you didn't just throw parts at it. Did you follow a trouble shooting tree from the FSM?
At least in my experience it would be sheer coincidence for an ign. module to fail over night. Once again, if they're failing they usually show signs (mis, etc) as they are heating up. Did you check the connector to the module? Just curious, did you replace the capacitor? I'm amazed at the price you quoted for one, used to be a couple bucks....lol.
I maybe wrong here, but I'm assuming (hate that word) you tried to start the car and had no spark.....is that what brought you to conclude it was the ign. module?
At least in my experience it would be sheer coincidence for an ign. module to fail over night. Once again, if they're failing they usually show signs (mis, etc) as they are heating up. Did you check the connector to the module? Just curious, did you replace the capacitor? I'm amazed at the price you quoted for one, used to be a couple bucks....lol.
I maybe wrong here, but I'm assuming (hate that word) you tried to start the car and had no spark.....is that what brought you to conclude it was the ign. module?
Thread Starter
Safety Car
Joined: Jul 2004
Posts: 3,838
Likes: 30
This really sounds wierd to me. OK, let me ask the question, how or what brought you to believe the ign. module was the culprit?
...at the beginning when this started happening, i would (and still do) clip on an inductive timing light and crank the car and i get NO spark....then, i would substitute a spare known good coil and would still get the same results....at that point, i replaced the ignition module and got a spark, and would start....in each case where it would not start and with the absence of spark, i changed out the ignition module and problem eliminated for the time being..i also checked the connection on the module where it plugs in to be sure is good contact and clean...
I know you didn't just throw parts at it. Did you follow a trouble shooting tree from the FSM?
..not exactly, more of a process of elimination for spark production...i also remembered the old condenser distributors and had one go bad in the 70's on me which trashed my spark so, at this point is/was my first place to look....
At least in my experience it would be sheer coincidence for an ign. module to fail over night.i
i would run the car all day and shut it down, come out the next day and no start...ie module...
Once again, if they're failing they usually show signs (mis, etc) as they are heating up.
no evidence of that....
Did you check the connector to the module?
absolutely...and if it wasn't raining now, i'd be changing out the capacitor assembly....
Just curious, did you replace the capacitor?
no, not yet...have never done it...but will as soon as i get a clear day!
I'm amazed at the price you quoted for one, used to be a couple bucks....lol.
yeah, me too but, that is what the dealer said!
I maybe wrong here, but I'm assuming (hate that word) you tried to start the car and had no spark..
correct
...is that what brought you to conclude it was the ign. module?
see above
...at the beginning when this started happening, i would (and still do) clip on an inductive timing light and crank the car and i get NO spark....then, i would substitute a spare known good coil and would still get the same results....at that point, i replaced the ignition module and got a spark, and would start....in each case where it would not start and with the absence of spark, i changed out the ignition module and problem eliminated for the time being..i also checked the connection on the module where it plugs in to be sure is good contact and clean...
I know you didn't just throw parts at it. Did you follow a trouble shooting tree from the FSM?
..not exactly, more of a process of elimination for spark production...i also remembered the old condenser distributors and had one go bad in the 70's on me which trashed my spark so, at this point is/was my first place to look....
At least in my experience it would be sheer coincidence for an ign. module to fail over night.i
i would run the car all day and shut it down, come out the next day and no start...ie module...
Once again, if they're failing they usually show signs (mis, etc) as they are heating up.
no evidence of that....
Did you check the connector to the module?
absolutely...and if it wasn't raining now, i'd be changing out the capacitor assembly....
Just curious, did you replace the capacitor?
no, not yet...have never done it...but will as soon as i get a clear day!
I'm amazed at the price you quoted for one, used to be a couple bucks....lol.
yeah, me too but, that is what the dealer said!
I maybe wrong here, but I'm assuming (hate that word) you tried to start the car and had no spark..
correct
...is that what brought you to conclude it was the ign. module?
see above
Last edited by Da Mail Man; Jul 17, 2008 at 03:27 PM. Reason: misspellings
Le Mans Master
Joined: Oct 2003
Posts: 6,130
Likes: 2
From: seattle WA
Did you also ohm test the coil? all these tests, ohm testing that is, an important part of this is twisting the wires while checking the ohms. I know one of the guys suggested you check your alternator....sometimes the voltage regulator goes bad, it's job is to limit the alternators voltage to a preset value, which prevents power surges or spikes to other components...such as the ignition. I haven't messed with a voltage regulator since they were external components, ours are built into the alternator, but I can tell you this, at least on the old regulators...sometimes the points would stick....so it might not be a bad idea while you're at autozone to have them load test your alternator...free. Just some suggestions, because IF 8 modules failed, then some other component is causing them to fail!
Thread Starter
Safety Car
Joined: Jul 2004
Posts: 3,838
Likes: 30
Did you also ohm test the coil?
no, felt no need to.....
all these tests, ohm testing that is, an important part of this is twisting the wires while checking the ohms. I know one of the guys suggested you check your alternator....sometimes the voltage regulator goes bad, it's job is to limit the alternators voltage to a preset value, which prevents power surges or spikes to other components...such as the ignition.
i have had the orig alt replaced and have had two in already with the last one suffering a mechanical failure when the pulley shattered.....
I haven't messed with a voltage regulator since they were external components, ours are built into the alternator,
i know as i have rebuilt many in my time..
but I can tell you this, at least on the old regulators...sometimes the points would stick....so it might not be a bad idea while you're at autozone to have them load test your alternator
had it done before i walked out of the store, however this has happened with the last two alts i have had...
...free. Just some suggestions, because IF 8 modules failed, then some other component is causing them to fail!
...assuming that the wires did not get somehow mistaken prior to me getting the car, as in an earlier posts, all i can see for me to do it replace the capacitor (condenser) assembly and cross my fingers....
no, felt no need to.....
all these tests, ohm testing that is, an important part of this is twisting the wires while checking the ohms. I know one of the guys suggested you check your alternator....sometimes the voltage regulator goes bad, it's job is to limit the alternators voltage to a preset value, which prevents power surges or spikes to other components...such as the ignition.
i have had the orig alt replaced and have had two in already with the last one suffering a mechanical failure when the pulley shattered.....
I haven't messed with a voltage regulator since they were external components, ours are built into the alternator,
i know as i have rebuilt many in my time..
but I can tell you this, at least on the old regulators...sometimes the points would stick....so it might not be a bad idea while you're at autozone to have them load test your alternator
had it done before i walked out of the store, however this has happened with the last two alts i have had...
...free. Just some suggestions, because IF 8 modules failed, then some other component is causing them to fail!
...assuming that the wires did not get somehow mistaken prior to me getting the car, as in an earlier posts, all i can see for me to do it replace the capacitor (condenser) assembly and cross my fingers....
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
If you take the spark coil cover off and look into the extension where the wiring harness plugs go, the primary wires should have the yellow wire on the far left and the red wire on the far right.
Thread Starter
Safety Car
Joined: Jul 2004
Posts: 3,838
Likes: 30
.......UPDATE:
....i went to advance auto this morning and not only watched but actually did part of the test myself....i ran the ignition module through
15 tests and all said it passed......going out to check wiring and if the rain holds up, install capacitor/condenser assembly.....
....i went to advance auto this morning and not only watched but actually did part of the test myself....i ran the ignition module through
15 tests and all said it passed......going out to check wiring and if the rain holds up, install capacitor/condenser assembly.....
Last edited by Da Mail Man; Jul 18, 2008 at 12:14 PM.
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Thread Starter
Safety Car
Joined: Jul 2004
Posts: 3,838
Likes: 30
.....installed condenser assembly a few min ago.....as for the coil wires; a white ,red, and black wire comes from the coil....
white from coil goes to the white/connector (could be yellow!)
(or discolored) wire that plugs into the cap...(you know where) and
a white wire plugs into that.
red wire from coil goes to the red/pink (discolored) wire that plugs into the cap (voltage supply to coil).
black runs to ground inside the coil "housing"......
connector from side of ignition module runs externally out of cap and connects to cap and apparently can only go on one way and it appears to be correct...
and why do ya say that?..
Thread Starter
Safety Car
Joined: Jul 2004
Posts: 3,838
Likes: 30
.....well it's more of HOW ya said it and NOT what ya said....at any rate, there is not much more i can do at this time but, still suspect that the assembly could, has, may have something to do with the failures as that is all there is left......
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
w.a.g.
take coil cover off...connect a 12v bulb to power (@ batt or elsewhere) and ground to the black terminal inside the coil cover, leave it on for a minute or two...your VOM is not capable of making this test...a poor ground may have the coil secondary using the ign module as its ground.
Thread Starter
Safety Car
Joined: Jul 2004
Posts: 3,838
Likes: 30
take coil cover off...connect a 12v bulb to power (@ batt or elsewhere) and ground to the black terminal inside the coil cover, leave it on for a minute or two...your VOM is not capable of making this test...a poor ground may have the coil secondary using the ign module as its ground.
...+12vdc to one side of bulb,
...other side of bulb to screw/wire holding down black ground inside
coil cover,
since the coil is removed as one piece with the cap, where is the coil picking up it's ground from?..the distributor housing when the cap is screwed down?...
...that should make the bulb light as there would now be a complete circuit.......
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
remove only the coil cover, it's held on by two screws with 1/4" heads...if you're one of the few that still has a spark plug wire retainer on your dizzy (like me) you will need to remove that retainer to access the two screws...leave the dizzy cap (4 screws) and plug wires,etc on.
btw there should be red/black/ WHITE wires inside the coil cover and not red/black/ YELLOW.
with the coil cover removed, you will see four screws that hold the coil to the cap, and from one of those there MUST be a black wire or stamped metal conductor strip to the three-prong connector -- this is part of the coil secondary circuit (completes high voltage circuit that fires spark plugs)...the four screws that hold the dizzy cap down are not part of any electrical circuit.
btw there should be red/black/ WHITE wires inside the coil cover and not red/black/ YELLOW.
with the coil cover removed, you will see four screws that hold the coil to the cap, and from one of those there MUST be a black wire or stamped metal conductor strip to the three-prong connector -- this is part of the coil secondary circuit (completes high voltage circuit that fires spark plugs)...the four screws that hold the dizzy cap down are not part of any electrical circuit.
Last edited by redrose; Jul 18, 2008 at 05:43 PM.
Thread Starter
Safety Car
Joined: Jul 2004
Posts: 3,838
Likes: 30
remove only the coil cover, it's held on by two screws with 1/4" heads...if you're one of the few that still has a spark plug wire retainer on your dizzy (like me) you will need to remove that retainer to access the two screws...leave the dizzy cap (4 screws) and plug wires,etc on.
btw there should be red/black/ WHITE wires inside the coil cover and not red/black/ YELLOW.
btw there should be red/black/ WHITE wires inside the coil cover and not red/black/ YELLOW.
remove only the coil cover,***YEAH, I FOLLOW YOU it's held on by two screws with 1/4" heads ***TRUE...if you're one of the few that still has a spark plug wire retainer on your dizzy (like me) you will need to remove that retainer to access the two screws***N/A...leave the dizzy cap (4 screws) and plug wires,etc on.***OK, I FOLLOW YOU...
btw there should be red/black/ WHITE wires inside the coil cover and not red/black/ YELLOW. ***UNLESS I MADE A TYPO, YES, THAT IS WHAT I HAVE WHEN I REMOVE THE COIL COVER (W,R,BLK)....(some wires may discolor with age)....
ok, so, when i do this, what am i supposed to or not see?
Melting Slicks
Joined: Feb 2006
Posts: 2,753
Likes: 15
From: backwoods upstate ny
you may not see anything amiss...but when you hook up the 12v test bulb you should get a full/bright light, indicating that the wiring to ground from the coil is not corroded/ partially broken/ etc
Advanced
Joined: May 2006
Posts: 70
Likes: 1
From: Davisburg Michigan
I had an '86 with a similar issue - no spark, I changed the ignition module which fixed it briefly, then the same problem came back - I finally traced it to an intermittent open in the small wiring harness that goes from the 5-pin end of the ignition module out the side of the distributor to a larger 4-pin connector that connects to the harness running along the firewall.
This small harness has 4 wires, 3 of which connect to the ignition module, the 4th is grounded by a screw to the base of the distributor. (Sorry for the extensive description - Just trying to make sure we all know what I'm talking about).
Anyway, the act of replacing the ignition module jiggled these wires enough that it would work for a while, then act up again. I got to where I'd just tug on the wires and the problem would go away.
This small harness has 4 wires, 3 of which connect to the ignition module, the 4th is grounded by a screw to the base of the distributor. (Sorry for the extensive description - Just trying to make sure we all know what I'm talking about).
Anyway, the act of replacing the ignition module jiggled these wires enough that it would work for a while, then act up again. I got to where I'd just tug on the wires and the problem would go away.
Thread Starter
Safety Car
Joined: Jul 2004
Posts: 3,838
Likes: 30
......thanks for the reply....well, the light then would glow brightly as you say.....dim if bad ground as you say...however, i think it would be better to take an ohm meter to measure the resistance from the ground terminal on the coil to the distributor housing and look for high resistance...can also run an aux ground if high resistance exists.....