04.5 cummins problems

C

Cummins_04

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Feb 17, 2012
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Still haveing problems with truck after nozzle install. Runs rough, throttle hangs when in gear at aout 1000 rpm. Have had all injectors tested and they all look great. All the crosstubes are good. Everything is torqued properly. It seems like it has a miss to it. Now a few days before i put an Airdog 150 on and it ran great. I know they come preset with 15 psi, is that still enough after nozzle install? Also if i try to drain the water seperator with the truck running nothing comes out, but it does when the truck is off. The truck is not throwing any codes at all. Ive tried it with tuning and on stock and it makes no difference.
 
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so i decided to put stock nozzles back on and still has the exact same problem. Anyone have any ideas what it could be. Runs rough, smokes at idle, throttle will hang at 1000 rpm in gear. Need some help, dont know what else to do
 
dont have rail pressure gauge, yea ive checked the oil level and no fuel in it. The truck ran great then changed nozzles hasnt ran right since, havent even been able to drive it
 
could a bad rail pressure sensor be the problem, i dont really see how it would have went bad the same time i changed nozzles
 
if you have a scan tool handy i would check rail pressure could be bad rail sensor or stuck open prv or bad afc whos pump you running
 
prv? afc? it has a stock Cp3, I have an Airdog 150 lift pump
sorry im a newbie with all this
 
pressure relief valve and i believe its called an acutator fuel control the prv is on the rail its designed to make sure you dont bring rail pressure too high. i blocked mine off bc the more it blows the weaker it gets. and the afc is on your pump its the only wire that goes to your pump. how many miles on the truck
 
160,000 miles. Ive tried unplugging the fca and it maxes the rail pressure
is the pressure relief valve on top of the rail where the fuel goes in?
 
Yeah on top of the rail it just looks like a plug and if the Fca maxed out the pressure then usually it's fine. Have u ever replaced the pump before. I believe u have the same nozzles as me.
 
Could you have missed a copper seal that goes on the injector? Or maybe double sealed one or two injectors? This would move your injector closer to ,or farther from the piston, which would affect combustion rates of the cylinder. Just a thought.
 
I haven't replaced the CP3 before, ive had the truck about a year now. just put the airdog on a few days before the nozzles. I have industrial injection 100hp nozzles 30lpm
 
You will know if the PRV has been unseated if you take off the return line and there is fuel on top of the PRV.
 
yea i have checked to make sure that im not missing or have an extra washer on. Have used new washers evertime
 
Another thought, what about your injector wires? Are they all tightened down to spec? Are any of them worn through the insulation?
 
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