A bad lambda o2 would cause misfires and a poor idle, but the pouring white smoke is independent imo. Does the smoke have any odor to it? 16psi with a decent taper is no problem so i strongly doubt it tune related.
E88 N54 Alpinweiss/Coral Red/Motiv HTA 3586r Tial .82AR/Other stuff...652WHP
F30 N55 XDrive EBII