I was hoping for the easy fix too, so I disconnected the wastegate line. No change. Relatively slow climb to just under 6 psi. It rained for over 48 straight hours and everything is saturated. Today there's a bone-chilling wind (and still no sunshine to dry anything out) so I probably won't be getting underneath today! My prime suspect (naturally, the most difficult to access) is the up-pipe slip joint. It did not feel very tight at all, although as the wye traveled further into the female end of the up-pipe it was more snug. I did apply some copper RTV at assembly.