Diesel problems
CK5
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Diesel problems
If you can dig it out send me a pic I will probably buy it if in good shape.
I'll look around for it, pretty sure it's in the scrap pile.
I have the wiring diagram for an 89 diesel which I'm thinking is probably still pretty close to an 84. If so there, there should be a pink wire that is hot in run and start. It's an 18ga wire.
Do you know what it feeds normally?
I found a couple pink ones, one that powered the HEI which I originally used. It drops voltage too. I don't know how it started before.
This was the pink wire that fed the HEI, it's bigger than 18 gauge though.
and here is another pink wire on a connector.
and here is another pink wire on a connector.
I would have to look at my blazer tonight it's an '83 with the diesel. There should be a wire that used to go to the fuel shutoff solenoid on the diesel that would be a good ignition source I think.
Here's the diagram I was looking at for the 89 square body trucks. You can see the pink wire labeled "HOT IN START AND RUN" in the bottom right corner.
Just be careful with wires associated with glow plugs. I made a mistake when I removed the 6.2 in my 84 K5 and installed a 350. I connected the coil to a wire I thought was hot when it needed to be. Turned out it was for the glow plugs so as soon as the glow plug timer timed out, the truck died. 
I don't remember the wire color I used tho.
I don't remember the wire color I used tho.
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oh that's a nice fockin diagram! That pink wire coming off the ignition switch, I need to get a voltage reading from that when cranking.
that's the pink wire I'm holding in the first pic above, it drops to 1v when I crank the truck. Weird thing is that's the wire that fed the HEI on the old setup.
that's the pink wire I'm holding in the first pic above, it drops to 1v when I crank the truck. Weird thing is that's the wire that fed the HEI on the old setup.
I was wrong earlier about that pink wire, it should be 12ga. The other wire I noted, the pink/black wire, is 18ga.
If that pink wire is dropping voltage, it would make me wonder if the ignition switch is going bad.
If that pink wire is dropping voltage, it would make me wonder if the ignition switch is going bad.
Or that sketchy crimp is sketchy.
If you can find the pink/black wire you could see what it's voltage does. 18ga seems kinda small for the ignition coil, but maybe you could use it to run a relay.
I think I'll keep the relays either way. I would just rather have the key ignition triggering them over a switch that I have to energize every time I start/kill the engine.
That's almost gotta be pink and black. I don't see the pink wire going to a plug like that on the diagrams I have.and here is another pink wire on a connector.
The other problem I had with mine is some of the colors didn't look like they should be I'm sure due to age and exposure. I was able to trace them out to what they connected with to verify. Unfortunately if someone already did some rewiring on yours it will be harder to verify.
Looks to me like it has a splice at the bulkhead and one side goes to the ignition switch and the side that goes through the bulkhead ends up going to the fuel solenoid. I'm not real familiar with GM schematics.
One of those wires on that plug was energized when the ignition was on, again it dropped voltage when cranking. Bottom line, everything is losing voltage when cranking.
I was using acetone to clean black paint of wires yesterday, now that I have this diagram that is legible I'll look closer at it.
I also see an engine ground noted on that harness (left lowerish side), I have not ran across that wire which is interesting. The block is grounded and the battery is grounded.
If my truck was running, I would see what voltage reads on the wires that are supposed to be hot on start and run. Maybe the drop is normal, but I wouldn't think so. Otherwise what's the point.
What is the voltage on the purple wire that tells the starter to spin?
What is the voltage on the purple wire that tells the starter to spin?
The thing is, even a slight drop like to 10 volts and fitech won't fire the ignition. Guys that run the fuel system without timing control don't have this problem from what I read. As soon as they introduce the timing control, no start....
Haven't checked the starter signal, I'll put a probe on it tonight.
