Calling all 7.3 techs/specialists got a test

[aldo_45030]

of you skill and abilities. Heres the scoop i have a 2003 7.3 auto f350 that randomly will not start. I can say with certainty it is not the cps, HPOP oil level, batteries or air pressure of the tires. I am fairly certain it is either a sensor/switch or a wiring harness problem.
So here is my question ........what component in the HPOP system will not allow the injectors to fire without throwing any code ???

I think they are not firing because when it does start no black smoke belches out like it would if fuel was dumping into the motor.
I think it is a wiring issue because i have started wiggling them when it doesn't start and after a couple wiggles she fires up.
The problem is it is random and i can't wiggle each connection and crank the truck over at the same time. Needless to say i am by myself most of the time and have short arms.
I thought at one time it was the pressure switch in the head itself i had tapped it and she fired right up. I have sense ruled that out since it fail to work several times.

 

[jvencius]

What has you so convinced it's a HPO problem? If you're getting white smoke when cranking, I'd venture a guess that it could be a bad GPR, the fix for which takes 10 minutes and ~$60 at the International dealer...

 

[aldo_45030]

nothing comes out of the pipe but dissappointment. once she fires it is like there was never a problem. no smoke ....or at least that i can notice.

 

[CSIPSD]

Under valve cover harness, GPR, I can say with 90% certanty that its not your HPO system.

 

[jvencius]

nothing comes out of the pipe but dissappointment. once she fires it is like there was never a problem. no smoke ....or at least that i can notice.

Have you tried connecting the two big terminals on the GPR? The one time I had to do a parking-lot GPR fix, I used jumper cables, since I could connect the two ends of the same cable to the terminals for ~30 seconds, then hop in the cab and my PSD fired right off.

 

[aldo_45030]

ok i will try it next failure. are they cheap? its still under warrenty should i have them fix it my ded is $100...

thanks to all

 

[jvencius]

ok i will try it next failure. are they cheap? its still under warrenty should i have them fix it my ded is $100...

thanks to all

You can buy the International version for ~$60 or so. Iff'n I were you, I'd buy a spare GPR and throw it in the glovebox along with the wrenches to change it out (IIRC you need two different sizes but I can't remember exactly which ones). Heck, even if you had to buy the wrenches, a spare IH GPR plus two wrenches from Sears is cheaper than your deductible so I don't know why you'd go to the dealer for, literally, a 10-minute repair.

 

[Radarman]

I am not saying this is your problem, but when my truck started to act flakey and run sometimes and not others, after checking everything I could find, it turned out to be my PCM. See if you can borrow someones or get one from a wrecking yard to test it with.

 

[aldo_45030]

I think i will test it first next time she acts up. the glow plug lamp does light and turn off so i assumed it was functioning......as far as the pcm i sure hope not i plan on putting in a dp switch here soon and i can hear it now ......" you caused the problem ...blah blah blah". about your luck sir ..