I know this has been talked about everywhere but I have an ignition bug on my 69 I have a ready to run electronic distributor I have 12volts at the distributor Ignition seems to lose spark after running for 30 minutes in 70 deg and above When it’s cooler out below 60 it takes longer for this to happen Have changed the coil New distributor circuit board No change My wire harness on the car has a black wire with a checkerboard pink stripe on it no writting. this is power to coil and distributor This also is the original ignition wire just shortened only about 3 feet remaining Most of the harness has been redone but some of the wires were not replaced all the back to the block on the firewall So they were shortened and spliced into Now here’s the question dose anybody know if this is the resistor wire or just a standard wire everything I find the resistor wire is brownish in color or white/orange /ppl something Now for wireing diagrams 67 and 68 show the resistor wire I haven’t found a 69 diagram that shows a resistor wire being thier or at lest not labeled as one
If it’s as repeatable as you describe, I would make up a jumper with a dropping resistor installed. Then when it acts up , start eliminating wiring with this jumper. Tie the jumper directly from the battery to the coil. Then tie it to ignition swich, etc. I suspect you have a marginal connection that is temperature sensitive . My first reaction was the coil but you already changed that out .
The ign wiring harness is different for 9s. The resistance part of the wire is wrapped in the interior side of the firewall harness. You can't really see it. So the wire that originally ran to your coil is powered by the resistance wire. As to why your wire loses power after a period of time I couldn't say but it sounds like some electronic piece of equipment is being overheated to the point it stops working. Sounds a bit like a pertronics problem.
Firebob so the wires on the inside, never would of guessed that so it runs from the key switch to the firewall connector I was thinking that most of the harness has been redone And the left over wire may have been the resistor wire and after it heated up started making the voltage drop to the coil and distributor but if it’s inside the car I haven’t touched it but some has been under the dash before me wires cut and spliced So I need to remove it or bypass it And hokie1984 I haven’t tried that we use to start old cars that way all the time and jump the starter solenoid
I just pulled my wiring book out and I see where thier is black and pink and yellow from the to switch to the firewall connector piggyed on the same terminal out to the coil is one of these the resistor wire their not marked that they are
Yes. IIRC the blk/pink one is the resistor wire. The yellow one delivers power while the ign switch is in the start position. Then when released to the run position it powers through the resistance wire at about 9volts or so. This is the reason you connotation use the coil wire under the hood on a 69 to power an HEI.
In the past when changing out an old points type distributor with an HEI, I have found the resistor wire with 9 volts was fine for powering a 12 volt relay switch. Then from the relay to the HEI. Giving full voltage to the HEI. It’s an easy way to do it.
The relay, triggered by the orig coil wire, should work well but I have read that some relays require a minimum of 9 volts to trigger. So I guess it depends some on the relay you use but I think most will work.