[RocketSurgeon]

Hey, I'm having issues with a 2009 BMW X5 N52. Sometimes the car runs fine, but it will occasionally go into limp mode with the half-engine light, DSC light, and 4x4 light. The car will have zero acceleration until restarted. Sometimes the issue occurs immediately upon startup. It has a code 2D58 DME, Internal Fault: monitoring, nominal torque. I cloned the DME to rule out hardware issues, and performed a software update. The intermittent issue persists. I found large vacuum leaks at the valve cover which have now been fixed. It will pass a smoke test. It also has a tiny crack at the bottom of the rear catalytic converter, though fuel trims are fine. I believe the problems appeared around the time the alternator was replaced. I just did battery+registration. Any ideas on what may be causing this? Thanks in advance.