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Discussion Starter #1
Long time listener, first time caller. I have a 2007 3500 with a 5.9 6sp, 50k on a rebuild with ddp 40% overs, fass 165, arp studs, Hamilton 182/214 cam, stock turbo, efi live. The other night it was driving normal, then out of nowhere it felt like I lost the turbo. Giant clouds of smoke and had a really hard time picking up speed from 3rd gear on. Got home and pulled intake, turbo shaft feels normal, boots are all tight. Plugged in auto cal, have a p0191 and a p0148 code, so I am thinking it is just way over fueling, not lacking boost, which made sense to me because it ran ok on the top end. I replaced the FCA with no change. I'm going to try the rail pressure sensor next, but wanted another opinion before I keep trowing money at it. It starts fine and idles/ runs through 1st and second gear fine. I tried unplugging the pressure sensor at idle and it started sounding like a 12 valve, so I'm really not sure what it needs.
 

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Both of those codes are pointing towards you losing your rail pressure. Could be an electrical problem pointing to the sensor.

Id start by making sure your fass is delivering sufficient fuel pressure to the cp3 while idling and driving. Could be a problem with the pickup, clogged filters, etc. After that I would get a scanner that can watch rail pressure and watch those pressures and see what’s happening there.
 

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With the amount of black smoke I'm producing it's hard to believe it's underfueled, I could definitely be wrong though. Any way to test the fass besides letting it run into a bucket for x amount of time? And would it be possible that the pressure sensor is malfunctioning and getting a low reading, thus telling the cp3 to add more fuel, while thinking it's being underfueled?
 

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Black smoke is partially burnt diesel fuel. When rail pressure drops the diesel isn’t atomized as much as it should be and becomes partially burnt. So yes, it’s a possibility, but we’re blind without some readings on the low pressure and high pressure side while this is happening.
 

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Discussion Starter #5
7500psi idling, up to about 23500 doing a pull just now. Actual FP right in line with the demanded fuel pressure. Only hit 25 pounds of boost though.
 
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