The issue was resolved. I removed all the intake, chargepipe, FMIC, and cleaned/reinstalled it. Checked for leaks on all vacuum lines. Car has been running strong for 3 days. No CEL, no half-engine light, can floor it in 3rd/4th gear at 3k and no issues. Car is finally mechanically solid! Just needs some PDR and bodywork to be back in perfect condition. Honestly happy with the quarantine so I can get stuff done on the car. Might be selling my 335i today so more money for fixing up the 1er
