Originally Posted by Usmcmudslinger
Sounds fair and good enough... appreciate the help. Another question is it normal for the truck to seem "powerless" when is cold?
Well it's a diesel. Diesel does not have a spark to detonate fuel. It compresses a lot of air into a small space, injects liquid diesel, which then ignites. When just using compression to combust fuel, heat helps drive the burning process, as with any fire basically. Since the entire motor is still cold and the only thing making heat is the glow plugs and compressed air, the burn isn't as complete or powerful.
Also, the PCM will retard the start-of-injection process to help protect the motor. This way it gradually warms the block up.
The last thing that might be the reason for the lack of power is the ExhaustBackPressureValve. The EBPV is a butterfly valve after the turbo. It's sole reason is to close during cold weather running until the motor warms. It increases back pressure, making the motor work harder and holding in that exhaust longer to heat up the block a little faster, but still safely. Most unplug the actuator for this as it doesn't really help the majority of us.