Hey guys my truck started idling rougher and sounds like it's misfiring. It also seems louder at idle but could just be me. ive also noticed occasional longer cranking.

I checked icp it had oil in it so I replaced it. I have drained and cleaned fuel bowl and replaced filter.

I'm looking for opinions on what it could be.

I was thinking fuel pump or hpop?

 

I'm experiencing similar symptoms myself, along with reduced power. I'll be posting my own thread shortly.

Whether it was the problem or not, it sounds like you're ICP sensor was bad anyway, so it was a good idea to change it. Changing the fuel filter can't hurt, and I also tried that. In my case it feels like it made a small improvement.

Have you checked for loose injector hold down bolts? When the injectors start to loosen up, the truck will get louder (in a clackity-clack sort of way). Pull your valve covers and re-torque all your injectors. 135 INCH /Lbs, with the engine fully warmed up. Its pretty common for them to refuse to stay torqued down over time, once the original injectors have been disturbed.

As for fuel, you need to check your fuel pressure. That will require some adapter fittings, from Diesel O-rings, to adapt the ORB fittings on the fuel bowl to NPT, and then to a standard schrader valve fitting, found on most fuel pressure gauge tools.

You will also need to pull codes from the pcm. To do this you'll need either a professional scan tool, such as from Snap-On, or pc based or android based diagnostic software. This will also allow you to monitor the ICP, and determine if you have sufficient oil pressure.

 

Thank you for the in depth post! I ordered the fitting to test the fuel pressure what is optimum pressure?

I will I'll be pulling to check the injectors the engine has bout 10k miles on it from rebuild so maybe they loosened up.

 

Are you getting any codes? What is your Hpop pressure?

 

Fuel pressure 55 - 60 psi.

 

Hey guys sorry my brake lines rusted out so I have been working on them.

I have no check engine light.
I am hoping to get a scanner on it this weekend if my buddy is free.
I will let you know the results