08 lmm violently shut off no start

Dlogger

New member
Feb 9, 2016
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Cny
Ok guys I've been pulling my short hairs out trying to figure this thing out, so I thought id come to the best So this is where I'm at, the other day started my truck let it warm up as usual. Drove 2 miles down the road forgot something at the house and turned around, made it 300 yards after turning around and the truck violently shut off, hard enough for me to make sure I still had both my driveshafts Got it towed back home to find a small fuel leak in the return. Replaced that line as well as the suction while I was under the truck. Went to prime it and it wouldn't hold a prime. The truck turns over as it normally has just no fire. So I've herd that the filter head assembly is prone to leaking, so went to the dealer and picked one up. That came with a new bleed screw, filter, and wif sensor. Slapped that puppy on there and went to priming again, still won't hold a prime. It gets rock hard and a minute later it takes 3 pumps to get hard again. No codes have been thrown in this whole ordeal, not even any warning signs of any sort before this. I have an auto Cal but no scanner so I had a buddy come over and the only thing he could read for me with his hp tuners is rail pressure. Rail pressure was 10,000 at 3 seconds of cranking. No fuel leaks anywhere but what is odd to me is I can clamp off the return going to the tank and the primer will stay hard? I guess I'm looking for some input before I am forced to take it to a stealership and spend that kinda money. Any help would be appreciated

And I'm new to the forum from a long break so its good to be back, just not on this occasion
 

Dlogger

New member
Feb 9, 2016
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Cny
I'm not sure really, he was using his hp tuner scanner. He said it was 10k at about 2-3 seconds of cranking. That's about the only thing he could monitor with it. Ive disconnected the little u shaped hose off the drivers side rail and I've got diesel coming not from the rail but correct me if I'm mistaken its the cp3 and injector return?
 

carl.swoyer

New member
Jan 31, 2016
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Is the rail holding pressure? I had a similar situation and there is a pressure value on the rail. It was sticking open, allowed fuel to return to the tank. Had the dealership in Albuquerque replace it.

Carl & Christine, 2012 Landmark Rushmore, 2005 Silverado crew cab lt 8 foot bed 6.6 lly /Allison -custom dual exhaust-198000 miles !
 

Dlogger

New member
Feb 9, 2016
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Cny
Yes the rail pressure holds steady. I'm now wondering how to check injectors without the truck starting