Volvo: 94 940 turbo sputtering, turbo boost gauge, clogged catalytic converter

Question
’94 940 Turbo, 194k miles.  Sputters under a load when accelerating at 2000 rpms+.  Engine feels restrained and doesn’t want to shift.  In park/neutral it runs great.  Engine accelerates fine but turbo boost gauge on dash shows turbo is not engaging when accelerated even 3k+ RPMS.  Exhaust manifold gasket on one port was completely shot.  Took it to independent Volvo shop who advised turbo CBV diaphragm needed replacement and claimed this malfunction was the source of problems and caused vacuum issues effecting the shifting.  For the cost, he suggested a rebuilt turbo since this would include a new CBV diaphragm.  Engine now has freshly rebuilt turbo and new exhaust man gaskets.  However, sputtering problem still not fixed and now “check engine” is on.  When work was done, new plugs/cap/rotor/oil/filters were also installed.  Could it be a clogged catalytic converter?  Tranmission problem? How can I further troubleshoot?  

Answer
Steve,
This is a job that will require a test drive by someone that has some Volvo experience. Find another shop to help you. I would take a guess that there is possible an intercooler hose that has a leak in it or a hole in the intercooler itself.
A clogged catalytic converter can cause a similar problem. Disconnect the exhaust to see if that helps. I am not sure of the trans that will be determined during the test drive.