Mark & Debbie Mueller
Checking wide-open throttle at the dock may not necessarily reflect what you see underway. The vacuum pressure in the engine is usually dramatically different under full load conditions versus no load.
There is a vacuum operated device on the turbo I have always heard called a waste gate, Volvo calls it a turbo actuator. This device is a valve that controls the flow of exhaust gases to the turbine wheel. If the vacuum pressure is not correct the turbo will never develop full boost pressure. I am not sure of the D3 spec on vacuum but it might be worthwhile to try and measure it if the following does not work. You may have a vacuum leak somewhere in the system.
Take a look at the OEM Fault Codes shown on the Volvo multifunction display; see the attached PDF on how to retrieve those fault codes to see if any refer to the turbo. Next, take a look at the Volvo service bulletin regarding the turbo actuator – be sure to click on the “Comments” at the top of your PDF reader for additional information. It does take a little bit of effort to push the linkage causing the vacuum actuator and wastegate to operate manually.
Brass Ring A54