Volvo: PO 234 Overboost Error Code, volvo experience, vacuum tee

Question
Dear Ray,
I have been having trubbles with my 2001 V70 3.4T for some time now.  We replaced the Map Sensor and Vacuum Tee after finding crack in the end cap.  We thought we solved the issue, but the problem has reared it's ugly head again.  What happens is the turbo comes on very strong and then has a delay before shifting.  Then the check engine light comes on.

We are on clear what to target next and could use your expertise.

Regards,
Boyd

Answer
Boyd,
Go with the codes that are turning on the check engine light. Get the code and read the manual to follow the procedure. Don't over look reading any codes in the trans control unit. If the shifting is affected then the fault maybe in the trans and not the turbo. If that all fails have someone with Volvo experience go with you on a test drive so you can show hin the problem. This maybe one that will require a bit of hands on to identify the fault.