Hi All,

Experiencing a weird start/idle boost issue on my 2012 R60 ALL4 S.

On start up within about 10 seconds my boost drops off to vacuum pressure only, about 4 psig, if I restart it comes back up to normal idle boost of about 13.5 psig. Occasionally after a few mins driving it drops off again and I get the CEL and it goes into limp mode, stop and restart again CEL cancels and no further issues, happened this morning so I'll pull the code later today and share.

I've checked the MAP sensor, I have no leaks, clean MAF etc and the car generally performs very well. I have a NM module fitted running at +5 psig, an aFe CAI, latest DV with the ALTA spring.

I suspect a sensor but as it's intermittent it's hard to track down, also thought maybe vacuum/wastegate related but as boost immediately recovers after restart I'm not convinced.

Any insights / thoughts / suggestions welcomed.

TIA