Crank no start issue HELP

[big_stroker]

Have a 6.0 that will crank and not start. When cranking we see about 100 PSI ICP. We took the oil filter out and cranked and have LPO. We also pulled the ICP senser plug and tried cranking it and got the normal 1400 PSI but still wouldn't start. Any suggestions?

 

[big_stroker]

Changed IRP and it is running again.

 

[big_stroker]

Well it was running... drove it and shut it off and now it gets to 300psi ICP and 84% dc when cranking and wont fire.

 

[6.0 Tech]

Probably got a dummy tube blown out. Pump air into where the icp sesnor is with the o il fill cap and the intke boot to the turbo off. Listen while air is being pumped in to which side the leak is on. The ipr must be commanded to as close to 100% as you can get.

 

[ghohouston]

That, or the pump is dying, sending metal though the ipr. Id pull the ipr back out and see if the screen is blown off, if the air test doesnt show any leaks. Does it start up cold, but wont re start hot? If so, thats almost always dummy plugs/stand pipes, if they havent been updated. Pop the valve covers off, if any of the 4 standpipes/dummy plugs arent a 12mm allen, they should be replaced, because they have not been updated. The older style will either be a 10mm allen, or a 1/2" drive square.

 

[big_stroker]

So I replaced the front dummy plugs. Took the one back plug from the drivers side (took it apart first) into the Ford dealer here and said it didnt need chaned but I questioned it because it was very short? The one on the passenger side was long and i couldnt even pull it all the way out because of the air box.

So after back together with just the front 2 dummy plugs replaced it starts but still wont start once warm. Should i replace the back 2 stand pipes anyway to see if thays the issue even though the o rings looked ok. The o rings on the dummy plugs looked bad.

This is the first 6.0 i have ever worked on... i own a 7.3 and a 6.4 so bare with me lol.

 

[6.0 Tech]

What year? It is uncommon for stand pipes to blow the o rings, but not impossible. Since the oil goes straight through them, the o rings typically dont have issues. They do come apart in two pieces, which is what happened on the drivers side, and of course did not happen n the passenger. The passenger side you will have to take the rail off to get the stand pipe out, or try to get it apart and hope you dont *** it up if you plan to re use it.

If the truck has an 05+ pump (aluminumn cover with cast iron pump) the stc fitting on the pump is most likely blown out. If it has an 03-04 pump which has a cast iron cover, the seal could be pushing out of the pump, or the o ring sealing yhe cover to the pump could be going.

Could also have an injector to rail seal leaking, but that is also pretty uncommon, at least with a cold starting engine. Typically when those seals go it wont build chit for pressure at all.

Best bet will be to air test it and track down leaks. I believe the thread on the icp is 12x1.5 o ring, but im not positive on that.

 

[big_stroker]

Truck is a 05. Do you have to pull the pump to replace the stc fitting?

Thanks for the help

 

[03_PSD]

yes you have to remove the pump

 

[big_stroker]

So I took the HPOP out... How can I tell if the STC is bad or not? Or do I just replace it anyway?

 

[Rob D]

If you have done all the work and have the pump out in my mind its a no brainer to replace it for peace of mind if nothing else

 

[big_stroker]

If you have done all the work and have the pump out in my mind its a no brainer to replace it for peace of mind if nothing else

Kind of my tought as well. It already has the upgraded stc on it. Any chance its the pump. Everything I have read says the pumps hardly ever go out.

So just to recap, I have changed the IPR and the front Dummy tubes on each side. Will fire and run cold (Still don't run good till warm, been that way for a while) Once its warm it will run fine. As soon as you shut it off it will not restart until it cools back down.

 

[Rob D]

Have you tried starting it without the ICP sensor now that you replaced the IPR?

 

[6.0 Tech]

It is very rare for those pumps to die. I think i have replaced 2, one was a misdiagnosis, and the other was due to the guy having a bunch of water in his oil from a blown egr cooler allowed to seiyit. He got all new injectors as well after i told him about the water in the oil as he didnt trust them, and i had them out doing head gasketsw.

What oil filter are you sing? What oil, does it seem diluted? After all that you have chased, you may pull the stand pipes out for piece of mind and double check. It is not common to blow those o rings out, but it can happen. Also as stated above, try restarting with the icp unplugged, it may be wigging out. Did you check yhe ipr pigtail when you were swapping it? You may have an issue yhere that shows up when hot due to higher resistance. Finally, try air testing as you can chase your ass all day, but actually diagnosing is typically the easiest.

 

[big_stroker]

This isn't my truck its a buddies of mine. So he wanted to go ahead and change the HPOP and the stand pipes. So we are doing that now and will see that happens.

Also we have tried starting it hot with the ICP unplugged with no change.

I don't think it was the pump myself but he said while it was out he wanted to change it. After pulling the stand plugs I am almost betting that was the issue.

We also pressured the system before pulling the hpop and turbo earlier today and could slightly hear something from the passenger side but it wasn't like a obvious leak

I will have some feed back here in a while after we get it back together and fired up.

Thanks

 

[big_stroker]

Well we fixed the issue but now have a bad oil leak.

Going to have to find it in the morning.

 

[big_stroker]

So we are back to this. Fixed the oil leak... thought it was good. Now it still wont hot start. When cranking icp is 200psi and dc is 85% and it wont start. Replaced everything it seems. Dummy plugs, ipr, hpop, standpipes.

Cranking with the icp unplugged i se 30% dc and 650 icp

What else could it be?

 

[6.0 Tech]

Injector? Pressure seems kind of hi for a leaking injector top o ring, but it could be. Also make sure you check all of yhe plugs on the rail, ive never seen one leak, but they have o rings, so in theory they could. Pump air to it with the valve covers off and check.