6.7 Frustration

DISTURBED

DISTURBED

YEA WE RIDE THE SHORT BUS
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Nov 22, 2007
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Ok, I'm kinda at the end of my rope on this 6.7 fueling issue. Truck has 427k on it. I constantly got the P1011 and P0087 code. The stock original injectors finally started to give me issues so I swapped them for known good ones. The CP3 has been changed for a known good one and I'm still getting the P1011 just cruising and the P0087 under a hard pull. When the truck is cold it will build 24k rail pressure until the truck gets warm and it drops to 19k and sets the 1011 code. It won't set any code cold. Other that the truck ran flawless. So I swapped the rail plug for another one I have. Both have the H&S shim kits. So now it won't set the codes and builds 22k rail pressure hot but it long cranks cold and really long crank hot. All tubes were TQ to 37ft lbs and I have no leaks that I can tell. Where do I go now?? I thought about swapping the plugs back and see it the long crank goes away and codes come back. For the first 2 days after the injectors were swapped there was no issues any where.

Edit: truck has a new FASS 150 on it
 
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Have you done a leak down on it? I know you are leaning towards fueling, but maybe some other issues?
 
Leak down on the engine? It only throws fueling codes. Idles smooth as glass till it gets warm and sets the code then it gets a slight shutter in gear and it comes and goes as your setting there in gear. No smoke or vibration like a weak cylinder.
 
I've had this similar issue with a truck I was working on awhile back. It ended up being the injectors. when they got warm they would return to much fuel causing low rail pressure code and fuel delivery under work. Might just have to bite the bullet and put new ones in.

Might check your fuel pressure to the cp3 to eliminate that.
 
Did you use new connector tubes? Do an SOS and see if there's excessive fuel in the oil vs. hours.
 
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Its never a bad idea doing a compression test on a 400k mile engine when to try diagnose hard starts especially when warm. After of course doing an injector return rate test to see if injector health has to do anything with those codes. Just a couple ideas off the top of my head. Good luck
 
I would guess high returns from crossover tubes or injectors. I had a truck that had a failed high pressure rail. It was cracked across the seat of the rail plug and once warm it would have these same issues. This isn't possible on the 5.9 rail as it actually reliefs through itself but on the 6.7 it reliefs to the side of the rail. Pull the line from the side of the rail and isolate it so that you have a clear view at the rail relief fitting. Try to keep fuel from the return line from getting out by plugging somehow. Shouldn't be any fuel come out of the rail at all at the return. The rail I had fail was a high mileage unit as well, being around 800k miles.
 
RascalMafia said:
Did you use new connector tubes? Do an SOS and see if there's excessive fuel in the oil vs. hours.
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I used the ones that were in the truck. When I started having issues I didn't have time to order a new set. It's on my list.
YoungDiesel27 said:
I would guess high returns from crossover tubes or injectors. I had a truck that had a failed high pressure rail. It was cracked across the seat of the rail plug and once warm it would have these same issues. This isn't possible on the 5.9 rail as it actually reliefs through itself but on the 6.7 it reliefs to the side of the rail. Pull the line from the side of the rail and isolate it so that you have a clear view at the rail relief fitting. Try to keep fuel from the return line from getting out by plugging somehow. Shouldn't be any fuel come out of the rail at all at the return. The rail I had fail was a high mileage unit as well, being around 800k miles.
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Interesting. I checked it this morning and I have fuel laying under the rail on the intake plate but no injectors leaking around where the fuel is.
pushlar84 said:
Iv seen the lift pumps cause that p0087 on the 6.7's
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has a new fass 150 on it and I do need to put a gauge on it to write that off as an issue
 
Mine wasn't leaking externally. It was leaking internal across the relief valve seat and trust me I had lots of hours in finding the issue. I've seen it many times where the lines meet the rail have a leak due to some contamination being on the seat when the line was installed.
 
YoungDiesel27 said:
Mine wasn't leaking externally. It was leaking internal across the relief valve seat and trust me I had lots of hours in finding the issue. I've seen it many times where the lines meet the rail have a leak due to some contamination being on the seat when the line was installed.
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I may try and pull this apart and see what I find. Definitely have a leak at the rail but none of the lines appears to be leaking. I may wrap a rag around it and run it up the road to see if I can pin point the source
 
Appears it has developed one around the rail. It didn't appear till I swapped rail plugs and started holding more rail pressure
 
DISTURBED said:
Appears it has developed one around the rail. It didn't appear till I swapped rail plugs and started holding more rail pressure
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Lavon posted about a similar issue awhile back that ended up being a hairline crack in the fuel rail. Didn't show all the time only under high load and heat. The frustration cost them a bunch of time and parts troubleshooting. I believe the tool to fix it involved an abrasive chop saw to the old rail so it could never be used again.
 
either way, check return rates on injectors, graph them and compare cold vs operating temp. text me if you have questions or anything else.
 
Freezingsystems said:
Lavon posted about a similar issue awhile back that ended up being a hairline crack in the fuel rail. Didn't show all the time only under high load and heat. The frustration cost them a bunch of time and parts troubleshooting. I believe the tool to fix it involved an abrasive chop saw to the old rail so it could never be used again.
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I remember this as well.
 
DISTURBED said:
Appears it has developed one around the rail. It didn't appear till I swapped rail plugs and started holding more rail pressure
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Unplug the FCA. If the rail is leaking, you'll find it. Be careful.
 
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