LBZ Surging

[Bravo Whiskey 21]

Stock 2006 LBZ 190K. From a dead start , standard acceleration, 1st and 2nd gear feel typical, shifts into 3rd and if or when the RPMs hit about 2K get noticeable power surge. Coming up on a fuel filter replacement so swapped in a fresh one. Still doing the same. I have owned this truck from brand new and it feels different. nothing else appears wrong. I have been driving my 3500 van that is a gasser most of the time as I work out of that truck so maybe it is me. Any thoughts ? Thanks in advance.

[More Power]

Sounds like it may be due to either fueling or turbo boost pressure variations.

In either case, codes should be set if the variation is outside of allowable limits.

A good tech with a Tech II scan tool can evaluate both fuel rail pressures and turbo operation on a ride-along.

[Bravo Whiskey 21]

Found out that the turbo has an issue. Computer talking to solenoid, solenoid is good. Turbo only operating at 17%.
Need to tear it down to see the turbo I guess?

[a5150nut]

What shape is your air filter in or have any critters moved into the housing?

[Bravo Whiskey 21]

All filters are GTG and changed regularly.
Shop is telling me that it is the Turbo. Local GMC shop stated that is not uncommon and they stock several units just for that reason.

[DmaxMaverick]

All filters are GTG and changed regularly.
Shop is telling me that it is the Turbo. Local GMC shop stated that is not uncommon and they stock several units just for that reason.

This is the result of continuous, poor diagnostic practice. A failed turbo is NOT common, although shops and dealers do replace them frequently. The turbo (the turbine and compressor unit), (as opposed to "the turbo", the turbine, compressor and conglomeration of parts that attach to it), in fact rarely ever fail, and normally last the life of the engine. I'm not saying your turbo has not failed, only that it is unlikely at this point, with such an inadequate diagnosis. Many "shops" and dealers have become no more than parts-exchangers, with little actual practical diagnostic experience.

Ask the shop and dealer for the list of DTC's they are basing their conclusion, and post them here, if you don't mind. If they can't/won't, then we are wasting your time, as are they.