truck wont crank with the key, but it will if i jump the starter posts. the yellow wire w/blue tracer to the posotive post will crank it over also, all the gauges work, fuel pump runs, glow plugs run, pre-buzz comes on.

im at a loss every wire is right, i tried putting it in neutral and still nothing. tried unplugging the fan clutch too, still no go.

any suggestions? ive read a few threads about this same issue but they never get answered

any input is appreciated!

 

I know there is a starter relay, either in main fuse box or in box under the hood, I will see if I can narrow it down for you.

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OK, everything I see says it's Relay 2163 in the upper right hand corner of the fuse box under the dash by your knees.

 

Already swapped it with the fuel pump relay and still nothing!

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ok i figured it out, had to unwire 4 miles of aftermarket alarm bullsh*t and it cranks now but no start!
ficm has 48 volts and 47.5 cranking, batteries are brand new, passes a buzz test, gettin fuel and wont start, passes pcm and ficm KOEO tests. no codes at all!

 

when did all this happen? suddenly or after some other work was done? Not the first time an alarm system caused problems.

 

well the story is long... its not my truck and i re-installed the motor for the gentleman. It ran fine 4 months ago before it was pulled apart. i completely unhooked the alarm nonsense and hooked the ignition wires it was hooked up to. eveything has power i mean everything all fuses/relays work and have the correct power (took me 4 hours, alldata, and the good ole power probe but i checked everything!!)

 

Most trouble with the alarms is after the batteries were disconnected for an extended period. Are you getting any smoke out of exhaust now when trying to crank? Make sure the FICM is plugged in good, the connectors should "click" when connected properly, One other thing to check on the 03 trucks is the Butterfly valve under the intake elbo, they are known to stick and truck will not start without air,the butterfly should be open, I would do that first.

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Also remember that if you had the oil rails off the heads that it will take alot of cranking to get it running,takes a while to get the air out of them. It is a good idea to have a good battery charger hooked up because the bats. will be dead before you get it started.

 

no smoke out of the exhaust, and the butterfly valve is working. ficm plugs are all snapped in, oil rails were never off but thanks for the info. im at a loss here

 

No smoke, No fuel? check fuel pressure

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opps, didn't read the whole post

 

its got fuel pressure i cracked the line off the top fuel filter housing and it sprayed like hell, ive ran into that issue with other 6.0s and it throws a injector circuit low code on every cylinder.

 

I think it might be a high pressur oil problem. Why was the motor pulled anyway, you can keep it short.