Any ideas?

[coldturbo]

After i finished installing a chargepipe my car (2015 F82 M4) starting acting strange, the exhaust got very loud, and no boost
Threw these codes.

120408 - Charging pressure control: Switch-off as consequential reaction.

121001 - Boost pressure sensor, electrical: Short circuit to B+.


My mechanic said my valve cover was missing the “gasket flange” after he did a smoke test, but the car was driving fine before the JPipe install..
Im certain I disconnected something although the flange missing is definitely a problem, i dont think its the main issue.

What do you think?