Painless/spark problem

[taildragger]

Ok I am trying to fix a buddies Jeep. He installed a painless wiring harness and work fine until one day his jeep would not start. Come to find out that it was not sparking. Installed new ignition mod and seemed to work. so now we have gone thru 3 ignition modules and maybe a coil. what happens is that we install the new stuff and then drive it and everything is fine and then shut it off and go to fire it up again and there is no spark. Is it possible for those modules to get to hot and burn up or the coil to burn up?? I am at a totally loss, installed in module today fired up and got the cob webs out of it and drove to the gas station to get some fresh gas in it and then went to fire it back up but no spark. Any help with testing a ing mod or coil?
thanks

 

[Jimbos76cj]

Did the resistor make it into the system? I'd look into maybe doing the Stealth HEI conversion if you keep frying modules. ALso I think that all modules are not built the same. If you are using cheapo boxes you may have an issue with them too.

 

[Torxhead]

Testing icms can be iffy, a bad one will get hot to the touch, the vehicle will have an ignition miss or not run at all. The best way to kill an icm is not to ground the black wire coming out of it. AMC connected the that ground wire to the distributor, but the best way would be to run it directly to the battery negative terminal. A coil should get 1.35 ohms across the two outer posts.

 

[taildragger]

I believe he took the Resistor out of the harness. We have talked that it may be the issue but like I said he doesn't live here anymore and I am kinda stuck trying to fix it or find out what is wrong and I'm no the best. I have a diagram that shows the resistor so I am going to look at putting it in the system. I really appreciate the replies and the help.
tm

 

[Torxhead]

That resistor wire has a NAPA p/n of icr22, I believe, the resistance is 1.35 ohms, this should give you 6 volts at the coil. They are a bit on the long side and if you shorten them up it will increase the voltage to the coil and icm, I have shortened mine years ago to check at 9 volts wih no issues. Another option is to use a diode, Radio Shack p/n 276-1143 with conventional wire. If you just use a conventional wire alone the current will back feed and give you ignition run on, plus it is hard on the cheaper icms and coils.

 

[Jimbos76cj]

you can also pick accel brand resistors from autozone.