Ant
Well-Known Member
Howdy everyone, this may be a long read.
Since my daily driver POS Ferd is down, I needed something to use to go pick some autoparts. So, why not use my 225 slant 6 73 Dodge Dart? Well I tried, but there seems to be no ignition while it's cold out and yes, we have fuel. Okay, well, I checked everything in the ignition system except the newish plug wires that I had installed and everything else seemed fine, but the voltage from the pick up seemed low. Ok, for good measure I replaced the pickup and the car fired up, that's awesome, but it was a false hope.
The next day while I was leaving work, it was cold and the car would not start. Now Im at the point of being stumped. So while cranking I get no spark from the coil wire, but I did get a very weak little shock in my hand on the end. "Wait one sec" I thought to myself. That should a much stronger shock than that, it should hurt, but it does not. The suspect is now the coil to distributor lead, hmm... So I check the resistance with my multimeter and find that this short little cable has an impedance of over 12K ohms. That is way more than I would like for a one foot long spark plug cable, so I got an old used Standard cable that was twice the length and check that. It was 6K ohms, hmm... ok. Back at the car I tested the coil again, but this time I had the lead off and the tip off my test light about 1/2 an inch away from the plug and confirmed that the coil was good with a nice big, bright and beautiful blue spark jumping to my test light.
So, using the 6k ohm lead, and a bit of less of cranking the engine fired up. Ok, now I'm starting to get an idea of what may be the reason for the hard and sometimes no start in colder weather. It's because of aliens. Just kidding. It may be the crappy spark plugs wires I had bought(I forgot the brand). I've always had problems with starting in the cold and would think the issue was fixed after replacing one other part, but it was warmer right after that so it seemed like the repair worked. So it could be a false hope created by something I could not see. Because who checks new plug wires?
The car started today too with no problem with the new old 6k ohm lead.
I know what some people are thinking. That over 12K ohms per foot is fine for a spark plug wire! Well, no, not for this application and when it gets cold it may give problems. I ordered a new set of magcore wires which should have a much lower resistance per foot than my old used wires that I have for spares and testing purposes. If this does not work then I have no clue of what else to do because everything else works as it should.
Also before people start claiming the ballast resistor, primary side wiring, or the ECU/ICM is the issue. The primary circuits may not be perfect but they all work as they should and I have 3 working coils and 3 working ECU modules.
(I hope the wiring harness is fine)
Since my daily driver POS Ferd is down, I needed something to use to go pick some autoparts. So, why not use my 225 slant 6 73 Dodge Dart? Well I tried, but there seems to be no ignition while it's cold out and yes, we have fuel. Okay, well, I checked everything in the ignition system except the newish plug wires that I had installed and everything else seemed fine, but the voltage from the pick up seemed low. Ok, for good measure I replaced the pickup and the car fired up, that's awesome, but it was a false hope.
The next day while I was leaving work, it was cold and the car would not start. Now Im at the point of being stumped. So while cranking I get no spark from the coil wire, but I did get a very weak little shock in my hand on the end. "Wait one sec" I thought to myself. That should a much stronger shock than that, it should hurt, but it does not. The suspect is now the coil to distributor lead, hmm... So I check the resistance with my multimeter and find that this short little cable has an impedance of over 12K ohms. That is way more than I would like for a one foot long spark plug cable, so I got an old used Standard cable that was twice the length and check that. It was 6K ohms, hmm... ok. Back at the car I tested the coil again, but this time I had the lead off and the tip off my test light about 1/2 an inch away from the plug and confirmed that the coil was good with a nice big, bright and beautiful blue spark jumping to my test light.
So, using the 6k ohm lead, and a bit of less of cranking the engine fired up. Ok, now I'm starting to get an idea of what may be the reason for the hard and sometimes no start in colder weather. It's because of aliens. Just kidding. It may be the crappy spark plugs wires I had bought(I forgot the brand). I've always had problems with starting in the cold and would think the issue was fixed after replacing one other part, but it was warmer right after that so it seemed like the repair worked. So it could be a false hope created by something I could not see. Because who checks new plug wires?
The car started today too with no problem with the new old 6k ohm lead.
I know what some people are thinking. That over 12K ohms per foot is fine for a spark plug wire! Well, no, not for this application and when it gets cold it may give problems. I ordered a new set of magcore wires which should have a much lower resistance per foot than my old used wires that I have for spares and testing purposes. If this does not work then I have no clue of what else to do because everything else works as it should.
Also before people start claiming the ballast resistor, primary side wiring, or the ECU/ICM is the issue. The primary circuits may not be perfect but they all work as they should and I have 3 working coils and 3 working ECU modules.
(I hope the wiring harness is fine)
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