Here's the low down. 94.5 powerstroke bought it with 190k. will not start cold, plug it in and she'll crank up. Guy I bought it from said he just replaced glow plugs and gpr, tested gps and they rread .001 ohm, crossed gpr and for 25 seconds (no change). I went thru and found some bad plugs and replaced them and she started and ran like never before but only for one day. Now I've got the valve covers off and tested gps and harness plugs still reading good. found one wire not gettin fire(Is that enough to make not start?). Wondering now if the glow plugs are cheap ones and that could be causing missing, but when I hot them connected the first time she ran like a striped ape.

 

I think you are on the right track thinking the harness is bad. If the GP's and relay are new and you've already identified one short in the harness there is no reason to think there aren't more. I'd replace both the harness's and see where you stand.

 

Scott I posted in this thread early but my post is gone. Any ideas???

I would agree but one thing that has me wondering is your ohm reading. .001 ohm is an extremely low number. Do you have the meter on the right ohm scale? may not matter if its autoranging.

 

Nevermind my response was in the other thread!