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Discussion Starter #1 (Edited)
I know there’s a ton of posts about this but I got tired of searching for one that applied to me.

On my way to work this morning my ‘Burb died when I accelerated at an intersection after the light turned green. I’ve had issues with my injection pump not restarting once it gets warm so I only drive it to work in the morning and home afterwards. I was able to coast and get to the side of the road and poured water over it to cool it down but still wouldn’t start. This has worked in the past and is how I troubleshooted the IP to begin with. So now I don’t use it to run errands anymore just my work commute. Anyhow, I wait and wait for it to cool down more but still nothing and that’s when I realize that the wait to start light is not coming on. So now I go fuse searching and that’s when I found the blown fuse. I go and buy a pack of fuses (not sure what happened to the fuse kit that belongs in there) and as I’m putting in the new one in it blows again. I didn’t even get it pushed in all the way. Just to make sure it wasn’t from the way I was inserting it, I put another one in and same thing. I unbolt the FFM and disconnect the 2-wire connection and same thing. So I disconnect the other one and still the same so I towed it home. Before I start tearing in to it I would like some input on what it might be. Also, I have Kennedy Diesel’s lift pump system installed and it’s operating just fine.

Sorry for the long post. Just wanted to give as many details as possible.

THANKS!
 

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Unplug the OPS connector and see if the fuse quits blowing.
The only things on the ECM-B circuit are the PCM and the LP.
 

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Discussion Starter #3
Thanks! I didn’t think of that because I also have the Kennedy Diesel OPS harness but that doesn’t mean the OPS hasn’t gone bad. That will be the first thing I do when I’m able to work on it again.

Thanks again!!!
 

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Discussion Starter #4
Unplug the OPS connector and see if the fuse quits blowing.
The only things on the ECM-B circuit are the PCM and the LP.
Well it’s done it again! When this did it last year, I saw that the connector was not fully seated to the OPS and was wet. Now, I took it out the other day because I hadn’t driven it for awhile and as I pulled into my driveway it went out again. I just went out to work on it and I replaced the OPS, since I had a new one already, while I was in there. Made sure all connections were good and pow, blew again. I unplugged everything. I know I was told that only the OPS and PCM were on that fuse but just to make sure, I pulled both FFM connectors, OPS and LP but still blew. Does that mean it’s my PCM then or am I completely missing something???

Thanks!
 

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I would start by going through all of your grounds.
Remove each one, clean the contact areas and reinstall.
If you find any that are in questionable shape, replace them
 

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Try taking off the fuel heater.
This is the cable attach to the FFM.
 

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The ORN wire on the OPS connector runs towards the Underhood Fuse Relay Center (UHFRC) thru the main harness.
There is a splice with 5 ORN wires in the main harness not far from the OPS.
2 go to the PCM, 1 to the OPS, 1 to the LP relay, and 1 to the ECM-B fuse.
There may be a short somewhere on that ORN (the ECM-B fuse) circuit.
These old harnesses have a problem with the wires melting together and having intermittent shorts, usually the wires with heavy loads.
 
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Discussion Starter #8
Thanks guys! I went out and pulled up on and jiggled the main harness and it quit blowing. I’ll open up the wire loom and look for the short. At least I got it moved out of the way for now. Thanks again.
 
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Thanks guys! I went out and pulled up on and jiggled the main harness and it quit blowing. I’ll open up the wire loom and look for the short. At least I got it moved out of the way for now. Thanks again.
Be sure to let us know what you find

(y)
 
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