First issues why this all happened is injectors 2, 3, 5, and 8 had horrible stiction. Used SnapOn Counselor to read the cylinder contributions. Truck has 287k miles.


So yesterday we rebuilt my trucks injectors and replaced all the o-rings on the rail, the ball valves, and the injectors, put new dummy plugs and stand pipes, cleaned the IPR and the screen.
After cranking for a little while to get the air out it cranked on and ran incredible. Like new. Let it idle for a few minutes and the truck had 200% better power when I moved it to fill the coolant reserve with water. Went to go drive it and it felt kinda sluggish. Went 1 mile down the road and when i let my foot off the accelerator it shut off. Could not get it started again.
After doing some of my own testing I noticed it shuts off when it reaches around 185 degrees. Will not start again until it cools off well below that.

 

Have you done an air test on it to make sure you have no leaks?

 

Just did it. No leaks.

But i borrowed the snap on counselor again. Cranking the ICP_PRESS slowly builds to 400 psi and then dumps pressure. Slowly builds up to 400, then dumps. This is with the ICP connected.
Unplugged, it and cranked it, it jumped to 779 psi. But no start.
Injector buzz test revealed no codes.

 

Did you do STC fitting? Have fuel pressure?

 

Unplugging the ICP throws a default PSI, thou it's usually a little higher. Shop air at 100 to 125 psi is not showing your leak. Like Randy said have you done the STC fitting? If you have anyway to put 400 psi to it (this is dangerous) the only other way is to recheck everything. It's not impossible but rare that your HPOP is going out. 2005 - 2007 are really reliable.

 

Have you checked the IPR? Pull it and look to see if it's fouled.

 

The truck started and ran ok before the injector work so im not sure if the STC fitting would be bad? Not sure. Not looking forward to it.

We pulled out the IPR and cleaned it and inspected. Made sure it had wd40 on it to help keep from sticking. Nothing chamged about how it cranks on.

 

But no i havent done the STC fitting. I guess after sealing up the system if the STC fitting and Orings were bad it would of blown it out or leaking now.

 

Just cranked on the truck. Took 10 seconds of cranking to get it started but shes running fine. Havent done anything new yet. First cold start of the day.

 

Let it run for a while up to temp,then hold it at 2000-2500 rpm and watch the gauges. see what it says and report back

 

ICP pressure readings

Cold idle:
RPM - 670. PSI - 660

Hot idle:
RPM - 700. PSI - 603

Hot revving:
1) RPM - 1500. PSI - 870
2) RPM - 2000. PSI - 1170
3) RPM - 2250. PSI - 1381
4) RPM - 2500. PSI - 1640
5) RPM - 3000. PSI - 2008

Revving down:
6) RPM - 2500. PSI - 1342
7) RPM - 2000. PSI - 1033

Then when i let my foot off the pedal, it shut off.

 

What was the IPR at hot idle and 2500rpm?

 

Cyl 2-3-5-8,, are all on the center Ficm plug. How far did you disassemble the injectors?

 

Run6.0 that's a great observation. I would like to know if the op observed any changes in ficm sync?

It almost sounds like the o rings on the nipple cups didn't seat right, which may or may not show on the leak test. Have the dummy plugs bean swapped to the new style?

 

That's great logic right there. I'm thinking along the same lines. Otherwise, I'd try running without the valve cover and see if I'd notice anything leaking significantly from under the rail.