bypass ignition module?

bypass ignition module?

Germy

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Cincinnati, Ohio
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1985 jeep cj7 360 20 rear and 30 front w/warn lockers 5 speed tranny,

1971 dodge dart built 318
installing a painless harness. got er cranking but no spark. do i have to use an ignition module? is there a way around it? there are two wires in one fitting and three in another. If they are needed, can someone hook me up with labeling what they are? distributor says motorcraft.

thanks!!!!!!!!!
 
Yes, you have to have an ignition control module of some kind or another. Without it the coil doesn't get a signal to send the 20,000 or so Volts it has stored up to the distributor. The stock ICM looks like this, and is mounted on the drivers side fnederwell.

jeep-cj-engine-ignition-control-module-5-7-8_250784725663.jpg


The distributor is going to say Motorcraft on it, so will the ICM, AMC got it's ignition parts from Ford.



On and Administrative note, please take the time to properly fill out your profile, like you agreed to do when you registered for this site. This question would be a lot easier to help you with if we knew anything at all about your CJ. What year it is, what engine is in it, stuff like that.
 
I put a painless harness in a CJ5 a couple years ago and the instructions that came with the harness covered hooking up the icm, and I think there was even schematics someplace in the paper work.
 
Blues, gotcha. Filled her out!!! Just need an avatar! Thanks for the info guys! I have been dealing with wires for too long, was hoping for a miracle! Lookin through the book with no luck. I'll do a search later tonight, 5 wires and I'm done!
 
Thanks :chug:

I don't know if this will help or not, but with the ICM, the two wire lead is the input and the three wire lead is the output.
 
That sir is a start! I am calling tomorrow, schematics are a little confusing. I cannot find a ballast resistor so I just bypassed it. I will be having adult beverages when this rats nest is complete!
 
i have a 76 CJ5 with a 304 its getting spark but it weak new disturber, coil, voltage reg, the guy i bought it off of said it needed a igntion module, but it looks brand new dose anyone have any ideas?? please helpp:(
 
i have a 76 CJ5 with a 304 its getting spark but it weak new disturber, coil, voltage reg, the guy i bought it off of said it needed a igntion module, but it looks brand new dose anyone have any ideas?? please helpp:(


If the guy says it nees a new Ign module I would get a new one. they can go bad pretty easy and wont show it. Ive heard horror stories of people getting them off the shelf bad. Buy one and if it doesnt work return it.. or keep it for a spare. Also double check all your wires. Hook a spark plug to your coil, ground it and crank it to see if it gets good spark. If it gets a good spark there place the same plug into a spark plug wire and ground it to see if it gets a good spark. you could have a dirty/worn cap and rotor, old wore out wires or bad plugs. Speaking of plugs have you checked the gap in them? if the gap is to big you will get crappy spark.
 
Heres what we have done today replaced the icm, distrubor cap and button. were getting great spark from the coil just no spark to the plugs the disturbor is turning and plug wires are new. i dont see what the problem could be
 
Heres what we have done today replaced the icm, distrubor cap and button. were getting great spark from the coil just no spark to the plugs the disturbor is turning and plug wires are new. i dont see what the problem could be
I think we may have hijacked a thread. If that's the case I apologize. If your getting spark out of the coil through the coil wire but nothing from the distributor cap to the plugs you have a problem in that area. How are you checking for spark from the distributor cap? You should be placing a properly gapped plug in one of the wires then ground the nut part of the plug to the motor or other good ground. You do have the motor grounded well right? If there is not a good ground from the motor to frame it may not get a good spark. Sounds like maybe a mismatched cap and rotor, bad ground, or??
 
we are checking spark like you said we also have a spark tester if it wasnt so nice i would roll off the hill!! lol ive spent over a huderend dollars in it today im fixin to convert to a single wire dist system weve checked the grounds there all good unless the wire is broke. i also am wondering how many wire are supposed to come out of the dist i only have one and have a exposed plug next to dist
 
we are checking spark like you said we also have a spark tester if it wasnt so nice i would roll off the hill!! lol ive spent over a huderend dollars in it today im fixin to convert to a single wire dist system weve checked the grounds there all good unless the wire is broke. i also am wondering how many wire are supposed to come out of the dist i only have one and have a exposed plug next to dist

You should have the main coil wire that goes right in the middle then there's 2 posts on it. I'm pretty sure there should be one wire hooked to each post. But again if your getting a spark front the coil the the ignition system is good. Try to put a small peice of something on top of the button on your rotor (clay, bubble gum, playdoh) then reassemble I to see if the the rotor is contacting the cap.
 
it is getting contact and the only spark we get is when we let off of the igntion there is only one wire coming out of the dist. and it is rigged but shount there be two wire coming out of the dist insteade of one. the button and cap are brand new and for my model cj i just have no idea why it isnt getting fire to the plugs
sorry for hijacking im just in a world of confusing
 
it is getting contact and the only spark we get is when we let off of the igntion there is only one wire coming out of the dist. and it is rigged but shount there be two wire coming out of the dist insteade of one. the button and cap are brand new and for my model cj i just have no idea why it isnt getting fire to the plugs
sorry for hijacking im just in a world of confusing



No worries.. At least your sticking with finding the reason it's not working.. Could you post or pm me a pic of the distributor and coil. So I can see what your working with? There should be 2 or three wires that come out of the distributor and plug into the ignition control module. Unfortunately I'm away from home for the next few days or I would post what mine looks like. There's a site that has good info. If I can find it I'll post te site
 
IMG_6238.jpg

Not what I was looking for but a pic none the less.. That's the factory plug for the dist. Do you know if it had a nutter bypass done. Either way those wires are needed for the distributor. The spark you see when you crank it may be from the starter solenoid, when you start the jeep there's a hot wire that jumps the starter solenoid to the coil. Once you stop cranking the only power it gets is from the ignition module. If the dist is missing wires it's not feeding the needed info to the ICM.. It's a pretty crude computer. You may need to get a new distributor or have yours repaired.
 
I'm going to go get a kit and make sure that the cap and button isn't mix matxhed if that don't work then I'm just going to the hei dist
 
I'm going to go get a kit and make sure that the cap and button isn't mix matxhed if that don't work then I'm just going to the hei dist

That's a good choice. Keep in mind the cheapo HEI dist will normally strip there drive gears pretty quick. When I get one for my CJ I'm going to take my old and new distributor to a shop and have my old drive gear put on my new distributor. This way both parts match up right and have the same type of wear to them. Good luck with it. Pm me if you have any more questions.
 
1985 Jeep CJ7 with strait 6...
All helpful info above, but not to me.

I took out my faulty Tach from my near perfectly running '85 CJ7 , replaced with a new one (Crown) and I get the same start/vroom, but no run!
At the same time I ALSO replaced the defective headlight switch (which turned out to be fine, it's the Hi/Lo beam floor switch that occasionally makes the headlights not come on). When I re-installed the new headlight switch, I inadvertently left it 'on', and saw a quick tiny spark when I inserted the blades into the receptacle. I also heard a soft click. BUT THE HEADLIGHTS WORKED (so it wasn't the lights fuses that clicked)!
And now I have the start/vroom, but no run. Can't find the ballast mentioned above (dunno if I even have one). Can't find the "30A fuse under the dash and separate from the main fuse box" also mentioned above either. And I'm not Sherlock, so
ANY IDEARS'd be MOST APPRECIATED!
 
That "Start/vroom" sounds like the secondary ignition is not working. There should be a red wire coming from the alternator and connecting to the "I" terminal on the starter relay. The motorcraft ignition in the later CJs do not have a ballast or a 30 amp separate fuse either.
 
That "Start/vroom" sounds like the secondary ignition is not working. There should be a red wire coming from the alternator and connecting to the "I" terminal on the starter relay. The motorcraft ignition in the later CJs do not have a ballast or a 30 amp separate fuse either.

Call me schtupit, but I am getting NOWHERE fast! I looked at the red wire you mentioned, and funny enough it had been spliced together. I was hopeful that was a problem, so I took it apart and re-soldered it... no luck there! It does beg a question though... that starter terminal, could it 'go bad'. I doesn't look like anything but a connector, but what do I know.
Okay, so I quite chasin' my tail tryin' to find a ballast & 30A fuse that didn't exist... THANKS!
I'm going to replace the Motorcraft Ignition Module tomorrow (already took it out and confirmed AZone has it in stock). I'm thinkin' on replacing the Ignition Coil with a basic Acccel, too; figure it couldn't hurt none!
Could there be 'relays' or other 'breakers' of sorts that went out? Like I said, she was running just fine before I changed out the Tach and the Headlight switch...
It's been said that 'many love a good mystery'...
WELL NOT THIS KID!
 

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