I was going to post this a while back and forgot!!!

[sam's 72]

A while back, I made a post about my truck missing. ( I tried to find the post, but I can't ) When I pulled the engine out I found the problem.

This is what it was doing. ( there was a couple of others on here that had the same problem )
Some days it would run fine. Other days, it would miss so bad, that it would shake at red lights. I had a GM HEI in it at the time. I went through every thing, new plugs, new plug wires, new cap, new coil, new rotor, new electronic modual ( under coil ) I rebuilt carb, still, some days it ran really good, then others it miss really bad.
Well, If any one is haveing this same problem out of theirs.
Check out the ingition wire goingto the HEI! Once I pulled my 305 ( V8 ) out, and put my 383 in, I had to change out a lot of the wires due to going with a serpintene belt set up from a 96 truck. When I pulled back the insulation on my ingintion wire, what I found was a burnt wire, with only about 5 strand of copper holding it together, it started out as a 10 gauge wire. it had enough wire to deliever the volts, to crank it up and run, but not enough wire there to carry the amps. I was always wondering why it would miss when AC was on.
I ran across a simular problem like this a long time ago. These kind of wiring problems will eat my lunch. My dad had a truck, one of the tail lights was not working. He replaced the bulb, still no go, so he thought maybe that bulb was bad, so he put another one in, still no go. He called me up and ask me if I would check it out, I went over, I hooked up my meter to it, it had 12.8 volts showing on my meter. I told him, there can't be any thing wrong, I put the bulb in, still no go, I put a bulb in that I new was good, still no go. I pulled the housing out the truck, when I was taken it out, I came across a spliced connection going to it, it was in bad shape, only one strand of copper was makeing contact, this given me 12 volts, but not enough amps to make the bulb burn.

Just wanted to share this with you guys, I know that there was a few people on here, that had the same problem I was having out of my ingintion with theirs, so I wanted to pass this along to them.
Sam

[Stocker]

Sam, that's an informative post, thanks for letting us know what you've found. Electrical problems can be quite frustrating. I bet you've helped a few people today.

[chickenwing]

I agree. Good post. Finding proper voltage would have stumped me. Being the "too smart for my own good" type I would have started pulling wires from all other accesories in the circuit to "narrow down my problem". Sometimes all the evidence is right under your nose. You just gotta open your brain to see it.