Ive got a 04 CC motorhome with 9.3 cat 400hp.The problem im having is very low power especially when cold,low boost around 10#'s,after running for a good 1/2 hour i can get up to 31#'s of boost.It also has a scan readout on dash and i can hold and watch tq the motor should be around 1350 and most ive ever seen is 770 and it feels like it.Ive taken it to CAT and another place and they say inj etc all checks fine,so after wasting money guess i'll keep trying myself.I did smoke system looking for leaks and didn't find anything.Boost seems right when warm but still no power?? Thanks for any help i can get.

sounds loke you havnt found the right mechanic yet.the laptop should tell exactly where the issue is.

Like what Rusty stated above. I understand what its like throwing parts at it. Smoke test will only do so much. The inter cooler has to be pretty much pressure tested by its self. Close examination of all any any hoses, Air to air, ETC
Just to mention a few, Turbo actuator/Turbo, Fuel filters. Do you know if this is a variable turbo.
Seen many in my days, waist gate issues with bad or week actuators. Seen a bunch of the variable units cause insufficient boost issues. The list is vast and wide for starters. When was the last time the overhead was run for example. I understand you are trying to save a buck.. Best i could tell you is to have a shop plug in and do a road test and look at the perimeters. You'll be money ahead.This have an Allison in it?

First off congrats on having a CC. If you haven't yet, go to http://www.irv2.com/forums/ Everyone is great especially in the CC owners forum. try in the cat section also. I agree with above the CAC needs to be checked for leak down after pressurized.

Get a hold of Mike Sprinkle up in Dayton area.use to race Beretta teal green.

My 14L Detroit has a variable vane turbo. On the way home, 6 states away, from purchasing it, mine lost boost and went into power derate mode. I bought a truck scanner from Amazon. I found the turbo was not working properly. A google search showed the turbo actuator was normally the issue, but after watching You Tube vids, I felt the turbo was bad. Put a turbo on and didn't fix it. I replaced the actuator(Vpod) and that took care of it.

I had one in particular where they were heading to Cordova for a big event. Got out on the call,did the filters first. checked the actuator. Low and behold, seized. Took a large bar and commenced to try to get it somewhat moving... Good luck with that... LOL. Got it moving a bit.. I'm not doing a turbo/actuator on the side of the road. He decided to turn around and drive back home close to 70 miles.>> 40 MPH. The problems with the variables is when the actuator goes to *** The turbo vanes get loaded with hard soot and can't rotate properly on the gate side.

The thing is out on the road i have 31 pounds of boost but still only 770 ft pounds of torque instead of 1350? Boost but no power still, just worse when cold.Ive spent 3k between CAT,Freightliner and Allison trans to say it's all ok and CC says the dash moniter is correct for output #"s?? Love the coach,but tired of these big places just ****ing me!!