I replaced the diverter valve, same problem.

The charge pipe was disconnected at first after I replace the turbo - metal clip wasn’t locked - but still low boost after that was fixed.

Had my usual mechanic do a smoke test and no leaks.

And the turbo had a brand new boost control valve and diverter valve.

And the other weird thing is my old turbo seemed to be fine, with no play in the wastegate or friction.