Misfire
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Yeah I'm sure it would be a ton of work. I did find one place that makes harnesses kwikwire.com but I'm hoping I can just find the problems easy and repair them. Because I already feel like I'm in over my head on this project and it's not worth what I gave for it.
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From: Virginia
Here are the diagrams for your truck.
1981 EVTM - ???Gary's Garagemahal
On page 18 in this link is your system correct? Start, Ignition, & Carb Circuits - ???Gary's Garagemahal
I think the next thing I would do is probe the white/lightblue wire going to the ignition box. With the key in run you should have 12v there. If it's very low, I would suspect the ignition switch, you could go back to it and probe some of those wires. You have a yellow wire feeding the ignition switch also.
If the white/lightblue is 12v, then I would suspect a wiring problem on that resistance wire in the diagram.
1981 EVTM - ???Gary's Garagemahal
On page 18 in this link is your system correct? Start, Ignition, & Carb Circuits - ???Gary's Garagemahal
I think the next thing I would do is probe the white/lightblue wire going to the ignition box. With the key in run you should have 12v there. If it's very low, I would suspect the ignition switch, you could go back to it and probe some of those wires. You have a yellow wire feeding the ignition switch also.
If the white/lightblue is 12v, then I would suspect a wiring problem on that resistance wire in the diagram.
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From: Taxachusetts
Test the ballast resistor wire as follows:
Separate the two wire connector ..the WHITE wire and the RED wire from the ICM from it's mating wires. Disconnect the coil's BATT (+) wire/horseshoe connection. Check the resistance from the ICM's RED wire mating (WHITE/lt bl) and the BATT (+) terminal on the horseshoe connection...RED/ltgr.
You're looking for a small amount (1.0 - 1.2 Ohms) of resistance. Any thing less or more than that, the ballast resistor wire boarded the last train to Clarksville.
Separate the two wire connector ..the WHITE wire and the RED wire from the ICM from it's mating wires. Disconnect the coil's BATT (+) wire/horseshoe connection. Check the resistance from the ICM's RED wire mating (WHITE/lt bl) and the BATT (+) terminal on the horseshoe connection...RED/ltgr.
You're looking for a small amount (1.0 - 1.2 Ohms) of resistance. Any thing less or more than that, the ballast resistor wire boarded the last train to Clarksville.
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From: Taxachusetts
Me Culpa! Wrong color on the BATT terminal.....went back and fixed it....
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From: Taxachusetts
In Franlin2's post # 21, on the wiring diagram....the resistor wire shows 1.1 ohms. I know there's a bit of leeway in these things.....so this might be an OK reading....?
Or it could be on the "HIGH SIDE" of "normal."
I'd hate to say to replace it knowing the work entailed in it...
A different test, same wire....Key ON (RUN position), Engine OFF. With the horseshoe connection back in place on the coil, test the voltage between the coil (+) and a good ground. I think Franklin2 had you do this one, correct? Any rate - you want to see ~ 6 - 8 VDC there.
Whatch got?
Or it could be on the "HIGH SIDE" of "normal."
I'd hate to say to replace it knowing the work entailed in it...
A different test, same wire....Key ON (RUN position), Engine OFF. With the horseshoe connection back in place on the coil, test the voltage between the coil (+) and a good ground. I think Franklin2 had you do this one, correct? Any rate - you want to see ~ 6 - 8 VDC there.
Whatch got?
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The ohms starting moving around as I was messing with the plug connector that carys those into the fire wall. So now I'm gonna see if I can find a new plug and replace it. To see if that fixes the issue.