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Discussion Starter #1
A few weeks ago my truck was having a hard time starting. It would crank for 5-10 seconds, and sometimes take a second time turning key to get it to fire. Once it was running, the truck ran fine. No loss of power, no smoke, drove like normal. Last weekend when leaving store it took several times to crank it over before it finally fired and I drove home. I did some research on here and on ole google but could not find anything useful. Went back outside to fire it up again and now it won't start at all.

Truck has 147k miles, is tuned and deleted running a Fass 150 and still has factory CP4. I typically run it on a 120 tune and drive like a grandpa (for the most part) I replaced both batteries last summer, replaced both filters on the Fass150 in Sept (3k miles on them now) replaced factory fuel filter in November. My fuel rail pressure is 4400 while sitting, and when i try to crank it jumps to 6700. I have tried bleeding off the fuel line at the fuel filter valve to make sure there is no air in line. I am also throwing no codes. I don't think it is injectors failing as when the truck was running Sunday i had plenty of power and it drove normally.

I have spoke with a couple diesel shops and have not been able to diagnose anything over the phone with that information. I am going to try replacing the factory fuel filter tomorrow to see if that is where the fail is, but that is a long shot i am sure. If anyone has any suggestions I am all ears. Hoping to avoid the $150 tow and who knows how much for the shop to diagnose at this point if it is something i can fix in the driveway.

Thanks for the help fellas.

B
 

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The CP4 went out in my 2015 with no warning. It showed no codes. Hope for your sake, that’s not it. Had to go with another stock CP4, because we were on the road and about 1000 miles from home. If it ever goes again I’ll put a CP3 conversion in it. Good luck with it.


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Not sure (at least hoping not) it would be the CP4 if i am showing normal fuel rail pressure both at idle and crank. I could be wrong as I don't know the exact location of the sensor that reads the rail pressure.
 
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