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my dodge died in traffic ....6 months ago, just as if i shut the key off .i replaced the control module (did the conversion 18 yrs ago) and ,eventually it fired up. i drove it another 6 miles and shut it off and .it hasnt started since. what i have and what i did::::: its a 68 dodge A-108,318 ,auto. parts to date ,are,,, control module and its wiring plug,bal resistor,distributor assy, coil, starter relay and starter,ignition switch,dist cap,rotor and wires plugs, all the parts ,when tested seperately test good .but ,,i have a no spark problem.the module and coil are grounded and so is the engine block. i have 12v everywhere im supposed to but i can hold the coil wire and crank it over!!! man am i at wits end here, any one with any ideas?????
 

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When you say you can hold the coil wire and crank it over, does that mean there is no power coming out of the coil to the distributor? This would be a bad coil itself, also, do you have spark from the distributor to a sparkplug? If not, hall effect or distributor rotor or cap problem. If you have spark from all places, check fuel first, then verify TDC, timing chain may be the problem. That's the next set of checks.
 

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The older distributor pick-ups were an electro-magnetic component and not Hall-effect like later systems. Something has changed or something's being missed. Do you have a factory service manual from the era that the electronic ignition came from?
 

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I thought that is what they were called since 1972?
 

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There is a 4-wire and a 5-wire ignition module, and a Lean Burn system from late 1970s, so we need to know what you've got in there.

Ballast resistors are notorious for being bad right out of the box. Check the resistance across both resistors (electronic ignition had a dual resistor).

If you have a distributor that's of the vintage from early electronic (1972-1980s), it will have a reluctor with 8 teeth around the dist shaft. Those teeth line up with the pickup coil to fire the ignition coil. That gap between the reluctor teeth and pickup is CRITICAL. It must be set with a non-magnetic feeler gauge, and you should NOT rely on it being correct right out of the box. The gap should be .008 inches, if I recall correctly. Too big a gap means weak or no spark, too small a gap and a tooth will hit and chip off the pickup coil, which makes the ignition die.
 

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Discussion Starter #8
Bob Lincoln said:
There is a 4-wire and a 5-wire ignition module, and a Lean Burn system from late 1970s, so we need to know what you've got in there.

Ballast resistors are notorious for being bad right out of the box. Check the resistance across both resistors (electronic ignition had a dual resistor).

If you have a distributor that's of the vintage from early electronic (1972-1980s), it will have a reluctor with 8 teeth around the dist shaft. Those teeth line up with the pickup coil to fire the ignition coil. That gap between the reluctor teeth and pickup is CRITICAL. It must be set with a non-magnetic feeler gauge, and you should NOT rely on it being correct right out of the box. The gap should be .008 inches, if I recall correctly. Too big a gap means weak or no spark, too small a gap and a tooth will hit and chip off the pickup coil, which makes the ignition die.
yes,the reluctor gap is .008 checked with a brass feeler gauge.and i am,,,, or was running a 5 pin module .and yes i have a factory service manual .ballast resistor checks out.see all that checks out.but the stumper is even tho all components ,tested individually ,test good .but when i re install everything...no spark from the coil wire ( yes tryed three other coil wires too even checked them with a ohm meter)
 

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And the wire was checked all the way to the ignition switch? Of all the weird places for it to go bad, have seen many an ignition switch wiring get hot on the back of the switch. If no power on the positive side of the coil, switch is where the electricity actually comes from.
 

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Discussion Starter #10
dana44 said:
And the wire was checked all the way to the ignition switch? Of all the weird places for it to go bad, have seen many an ignition switch wiring get hot on the back of the switch. If no power on the positive side of the coil, switch is where the electricity actually comes from.
i replaced the ign switch and in doing this i checked the wiring and its ok.also when the switch is "on" there is power to all the places it should be. i even ran a wire from the bat. to the coil with no luck
 

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Ad nauseum, if you have power to the coil, power to the ballast resistor, do you have power out of the ballast resistor? If you can hold the coil wire against metal and get spark, good, if not, something is wrong there. If it is to the coil but not out of the coil, then the coil is bad, throw another one on there and see what happens, one of those known good old test pieces you need at times.
 

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Try running a wire from the positive post on the battery to the positive side of the coil and then jump the starter solenoid and see if it starts. If so, then you've got either a broken fuseable link or wire somewhere. Or so it sounds like to me, but I'm not a mechanic.
 

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What ignition module do you have? Description, part number?
 

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Discussion Starter #15
gents, it would appear that there are some 4 pin control modules with a dead 5th pin. this was my culprit,so be aware. take your ohm meter with you and check. the 5th pin should not be open .hope this helps
 

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Glad you got her fixed!
 
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