I think you should be seeing around 22-24 psig boost at full throttle in final gear in lockup... You will only see these numbers for a very short amount of time till the engine starts building HP & torque and the EMC will start backing off the turbo boost.
If the boost is low, do as others have suggested and check
all things connected to the turbo:
Air filter, air intake boot and hose to turbo, both boost hoses to and from the inter-cooler (CAC), all vacuum lines feeding the vacuum solenoid and vacuum canister, vacuum line from vacuum control to turbo diaphragm controller. Anywhere you could loose boost pressure or vacuum control to turbo!
Note: One member on here found his plastic vacuum line between the turbo and vacuum control solenoid had a small crack in it loosing vacuum to turbo, a.k.a. low boost!Other items to consider if none of the above are found to have a problem:
Does it still have EGR valve and flow control valve (FCV) on engine? If so, EGR can be stuck partly open and loosing boost through it (blowing boost back into exhaust). FCV gears could be broke, stuck partly shut not allowing full flow from turbo into engine intake manifold.
Last but not least: CAT (catalytic converter) could be partly stopped up not allowing adequate exhaust flow to leave turbo and exit to build full boost...
Check all these things starting at the air box.
Good luck! Keep us posted...
_________________
Supporting Vendor and Moderator of LOST05 Jeep Liberty CRD Limited
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Yeti StgIV Hot Tune
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No FCV/EGR
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Carter Intank-pmp
2mic.Sec.Fuel Filter
Flowmaster/NO CAT
V6Airbox/noVH
GM11 Bld.fan/HDClutch
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