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Long story, and bought the car this way, so please no badgering about going to carb. 87 t-top gt fox body, with 94-95 carbed 5.0. Originally had MSD pro billet distributor, still hooked to EEC, car started and idled fine, revved fine, and drove. Seeing as how it still had EFI parts on it, I proceeded to correct this. Duraspark distributor and module, pulled out all the EFI stuff. Now the car will run for about 10 seconds and die. It runs great, no missing, responsive throttle, just kills the module. I have replaced all grounds checked with volt meter. Belt is not on (need power steering pulley), so I don't believe it would be a bad volt reg from alternator. Also replaced the pickup in the dizzy, tried with a new coil. I'm running out of ideas. Thanks for any help provided.
 

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Also, I have installed an MSD 6AL 2, no longer works, same result as duraspark module. Also ran an HEI module, same results, car starts and runs for about 10 seconds.
 

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what do you mean, module blows up?

you say you have spark, but module is bad?

how are you testing the module?
 

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I do have spark initially, car starts, then dies. I should have worded that better, it's burning up modules. I haven't had the modules tested, but when I get another HEI module (it's how the ignition is wired at the moment) and wire it in, same result, car starts, runs great, then dies, it's about 10 seconds.
 

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I did come across a wiring diagram for my car as an EFI, and it's showing a ground from the ignition switch to the EEC. I suspect that may be the issue, the wire would no longer be grounded with the EEC out?
 

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wow, forgot an important part to my problem. No spark after the car dies. Sorry about that, working 18 hour days, pretty tired lol.
 

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in order to burn up a module prematurely, you must have a overcurrent situation on the primary side.

what is the current draw? and what is the module rated for?

a missing ground is not going to burn up a module.......no ground just means NO current.
 

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Did you install the resistor? It goes before the coil and the module?
I did not. Everything I've read says if you use an aftermarket coil, you do not need a resistor? I'm willing to give it a try though. I did decided to pull the dash just to check all my wiring. Found that the 12v with key on wire (red/green) had a piece of insulation gone, right after the fuseable link, and was corroded. Also, the connector to the ignition switch was a little cracked and swollen. I have replacements for both, doing that tomorrow. Thanks again for all the help!
 

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I did not. Everything I've read says if you use an aftermarket coil, you do not need a resistor? I'm willing to give it a try though. I did decided to pull the dash just to check all my wiring. Found that the 12v with key on wire (red/green) had a piece of insulation gone, right after the fuseable link, and was corroded. Also, the connector to the ignition switch was a little cracked and swollen. I have replacements for both, doing that tomorrow. Thanks again for all the help!

You may have more than one problem. Make sure your grounds (all) are good. The ground side of circuits are often overlooked but can cause a lot of problems. I've seen poor grounds result in engine harnesses and coil packs melted as well as a bunch of driveability problems. You could ohm out the circuit wires and check for continuity to pwr and ground. Don't check for continuity with the key on as it will jack up your readings. You could also do a voltage drop /load test the wires. Good luck!
 

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I did not. Everything I've read says if you use an aftermarket coil, you do not need a resistor? I'm willing to give it a try though. I did decided to pull the dash just to check all my wiring. Found that the 12v with key on wire (red/green) had a piece of insulation gone, right after the fuseable link, and was corroded. Also, the connector to the ignition switch was a little cracked and swollen. I have replacements for both, doing that tomorrow. Thanks again for all the help!
get the right tools, and measure current.........the current is what will destroy the module

if you don't have the right tools, bring it to a good diagnostic shop with the tools.

it is very difficult to diag this sort of thing with just simple tools.
 

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I did not. Everything I've read says if you use an aftermarket coil, you do not need a resistor? I'm willing to give it a try though. I did decided to pull the dash just to check all my wiring. Found that the 12v with key on wire (red/green) had a piece of insulation gone, right after the fuseable link, and was corroded. Also, the connector to the ignition switch was a little cracked and swollen. I have replacements for both, doing that tomorrow. Thanks again for all the help!
get the right tools, and measure current.........the current is what will destroy the module

if you don't have the right tools, bring it to a good diagnostic shop with the tools.

it is very difficult to diag this sort of thing with just simple tools.
Thanks again for all the feedback. Went through the entire harness under the dash. Replaced ignition switch, replace the power on with key fuseable link. Wrapped the harness back up, got the dash all back in. Started the car up, first hit of the key, died right up. Now, here's my next question and my scenario. I'm using the stock fuel pump relay, powered by the 12V key on wire (red/green) however, when testing the ignition, I just touch the fuel pump power wire to the battery before trying to start it, since the pump will constantly run. I realized today that every time I have hooked the fuel pump power wire to the red/green 12v power with key on wire, is when I seen to lose spark. Could the relay somehow be messing with the ignition since it's running of the same power wire as what runs the ignition module? Sorry for the book, is late and my brain is fried from working on the car all weekend. I may just have to take it to someone, as much as I hate to. I've always done all my own automotive work, and have done great, till now lol.
 
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