HEI 5 Pin module, no spark

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fried_daddy

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Is there anything that should be hooked up on a 5 pin hei module to get spark besides +12v on the red wire? I'm trying to test fire my engine on the stand and i'm getting nothing. It's a 4.3 v6.

I used a test light between the tach wire and +12v on the battery and I'm not seeing any flashing. I've also verified that the rotor is rotating in the cap.

I had them check the old module at o'reillys and they said it was good. I decided to go ahead and get a replacement dist just in case tge puck was bad.

So far, replaced distributor, cap and rotor. Using jumper cables to make sure dist has good ground and good +12v.

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76racetruck

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Try test light on tach wire to ground. Or not at all. Just leave the tach wire disconnected from everything. The only thing you haven't changed is the coil. did the distributor come with cap rotor and coil.
 

fried_daddy

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Try test light on tach wire to ground. Or not at all. Just leave the tach wire disconnected from everything. The only thing you haven't changed is the coil. did the distributor come with cap rotor and coil.

Yes, it came with a coil. The test light from tach to ground is illuminated when I have the +12V wire hot. Stays illuminated whether the engine is turning over or not. Coil resistance with it disconnected from everything is 1 ohm.

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fried_daddy

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A little more background that may help me get this spark issue resolved. My truck is a 87, which came with TBI. This motor came out of a 85 or 86, and I'm running it with a carburetor. Currently trying to get spark on the engine stand before I am set to put the motor back in my truck.

I thought with a HEI, all you had to do was hook up +12V to the red wire as hot when the Ignition was on and you're good to go. Is there anything different about stand alone wiring using the 5 pin versus the 4 pin modules?
 

fried_daddy

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Birmingham, AL
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Matt
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1987
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R1500
Engine Size
5.3 LS
**UPDATE**

After several hours of searching last night, I discovered that the 5 pin module is for ESC and you have to have the two outside terminals on the side of the module that has 3 terminals shorted together in order to operate as a stand-alone unit without computer control. I just modified the old connector that wasn't going to anything and soldered the A and C wires together. Posting this here in case anybody else runs into the same issue.

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