Proud New Owner

[LawStrokin]

I recently purchased a 2002 Ford F-350 Crew Cab Short Box 4x4 Lariot with 327k miles. This truck runs, drives and performs excellent. It has an AFE Stage 1 Intake, Manaflow 4 in. exhaust dualed out the back and a BullyDog 4 bank chip. This truck doesn't leak a drop of anything, smoke excessive or have any problems except when the truck is cold from 1200-1800 (about) RPMs the turbo makes a sound as if it was blowing out extra air not going into the engine and the truck kinda feels like its lagging. I live in Texas and we've been having temperatures about 15 degrees and it only does it when its this cold outside. When its warm outside and the truck is "cold" this doesn't happen. When the truck gets to operating temperature it runs great and this doesn't happen. Other than that there is NO turbo lag and the throttle response is great. I have off this weekend and I'm going to check intercooler boots etc. Is there anything else I should be looking for? Any other advice for me is greatly appreciated.

[SuperCrutyPS]

Congrats on the truck!!!

- Glad to have yo at the .org!

The cold issue you have is probably the EBPV (Exhaust Back Pressure Valve) being closed with the engine is cold(er). The EBPV closes when it's cold to keep heat in the engine to help it warm up. Not a 100% sure, but I believe it's in the output side of the turbo. So, it is restricting the exhaust some, hence the feeling of lagging.

[LawStrokin]

Thanks, I must admit, I've always been a Cummins man but now that I've had a chance to actually own a Powerstroke I LOVE it and don't see myself going back.