Are you really sure that the GPR is working? This (see red above) should go down to 11.5 volts when it engages. Also,Did you hold the screw driver across the posts for about 2 minutes?

Go to Wally world and get a digital volt testor (15.00) that you plug into the cig/power port.

1) The digital reading when plugged in should be 12.5 v.
2) when you turn the key on the reading should go to 11.5 (anything below 10.5v the truck will not start, ie bad batts)
3) if it does not go down to 11.5v, then the GPR is not working.
4) if it does goes down, cycle it through twice to heat the Glow plugs up nice and hot.
5) When (if) started the volts will remain around 12.5 until the GPR goes off and from there it should slowly climb to 14.5 (Alt output).

 

Great vid, that helps, mine did have that crisp sound. I did do a contribution test, results where low/unbalanced for cylinder 8. I don't know what perdel readings are, i remember seing it and think all were 0. I can check again if that doesn't make sense. Do you think #8 could be cause all this? one bad injector?

 

I have read somewhere that cylinder # 8 give some type of false or strange readings. Someone will come along with a better explanation.

 

That's good to know, I also think one bad cylinder would not cause all these problems, either. I'de like an explanation of the faulty reading if someone could please. Also what is perdel reading on the scantool?

the gpr test i did with a quality dmm:
+ on big post going to gp - on Batt.
gpr clicks and reads 11.5, slowly climbs to 12.5
gpr clicks again and reads 0v

batt reads 14v while truck is running

If there is something I've missed or doing wrong with gpr test it would dream come true (and a possiblity )

 

"the gpr test i did with a quality dmm:
+ on big post going to gp - on Batt.
gpr clicks and reads 11.5," Power is drawn down as GPs come on.. Good

"slowly climbs to 12.5" I assume you started the truck and voltage is normal...Good (If it is 'rising' to 12.5v before you start the truck then the GPR may not be staying engaged and defaulting to the batt level of 12.5 v or your GPs are not staying on.)
"gpr clicks again and reads 0v" GPR Shuts off....Good

"batt reads 14v while truck is running" Showing Alt output... Good (mine shows 14.5v)


All testing of GPR seems ok

 

I don't think one injector will cause the issue, the erroneous readings on cylinder's 3 and 8 are dependent upon the type of CPS that is installed, the grey CPS installed after the recall has been known to cause erroneous balance faults.

It does seem that your GP system is working. Just to verify we are troubleshooting a no start situation? Use your scan tool to monitor live data PID's to insure while cranking that Battery volts stay aabove 10.5V, RPM signal is atleast 100, and the ICP pressure reaches about 500psi?

 

that's good to know, I was wondering if I had to look into something there on #8

ICP spiked while cranking and idled ar 600psi

and yes it is a hard start/no start depending on how long its parked and how cold it is. I'm going away this weeknd and taking the family car, so I'll get back with some more readings monday. Thanks for all your help!

 

Here is a good guide for other things we might have missed, enjoy your trip, stay persistent and we'll get your truck worked out for you
This is a good "No Start" trouble shooting guide.
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Originally posted by Dave (Golfer) on PSN 01-20-2010 Thanks Dave

its nevvvvver the oil pump...seriously.

I see sooooooooooooooo many guys (dealerships included) that see "no ICP" or some ICP codes in a scantool...and toss HPOP's on truck after truck...when it is either an IPR or an injector (poppet valve) issue.

If you hook up the scantool, and monitor ICP (psi) while cranking...you'll see IPR% (duty cycle) climb & climb 15% key on..20, 30, 40, 55%, higher..the increase in IPR% means that the PCM is requesting ICP pressure to increase...

so ALSO watch ICP(psi) and if it comes up to only 180-250psi or so and stays there...then it's the IPR hung open (bypassing oil back to the oil pan through the front cover) such that only minimal psi can be made.

If the ICP is VERY low...like under 60psi...then it could be injector (poppets) pissing oil (under the VC's)..which is typical for injector with more than 180-200k miles.

if ICP climbs above 550-600..then it will probably climb much higher (15-1800+) and it is most likely going to be an electrical issue.

If his scantool will not connect then its a PCM or chip issue (remove the chip if you have one & haven't removed it yet)

if the scantool connects AND you have >600ICP then look at the datastream for a RPM reading.

if the scantool picks up an RPM signal and it seems accurate....then the CPS is good.

If no RPM on the scantool, replace CPS.

If you have RPM (on scantool, not just on dash)...AND have ICP >600, then run an (key on, eng off) injector "buzz test"...

the buzz test is nothing more than a continuity test from the PCM, through the IDM, and to & from each injector solenoid.

LISTEN to each inj buzz....do they all sound the same? nice & crisp?

if the test passes (and you audibly heard them all)...then wiring is good, IDM is good, HPOP is good...CPS is good...then it could be a fuel issue. gasoline, water, etc...

I wouldn't mention it if I haven't seen it myself numerous times...

any chance this no start began with 10-20miles after a fillup?

holler if you need help troubleshooting. take care~ Dave
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Hears some good info also:

7.3L Powerstroke Starting Requirements:
Battery voltage a minimum of 10.5 volts while cranking
RPM at least 100 while cranking. If no tach movement suspect CPS
If you have a scan tool ICP should be 500 PSI ± 25 PSI and fuel
pulse width should be 1 to 6 milliseconds.

The above requirements assume the following:

Correct oil level, oil type and pressure
Correct type of fuel
Correct fuel pressure (53 PSI per Ford spec)
Sufficient air supply (clean air filter & unobstructed intake)
Proper oil level in HPOP reservoir (1 to ¾ inch from top)
Proper glow plug relay and glow plug operation (in cold weather)
Proper injection timing (PCM controlled)