This would be easier to identify if you get some logs pulled. I'm going with the majority in saying its a leak in the system and if it is, logs will show AFR's out of the norm.
E92 '08 335Xi 6AT - JB4+MHD, ar design DP's, Race Cats in the mids, Corsa Axleback, VRSF CP w/Tial BOV, VRSF 7" FMIC, BMS DCI, BMS Cowl, H&R Coilovers, Renn Motorsport RS-51's, Alpina TCU Flash, Retrofit Earl's Oil Cooler, Turner Boost Gauge, Fully Coded.
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