{"nhtsa_id":10147696,"type":"service_bulletin","type_name":"Service bulletin","date_added":"2018-11-13","date":"2015-03-01","document_id":"M110708","mfr_campaign":null,"replaces":null,"component":"ENGINE AND ENGINE COOLING:EXHAUST SYSTEM:EMISSION CONTROL:CRANKCASE (PCV)","mfr_system":null,"summary":"Crankcase Ventilation System Diagnosis and Measurement. INFORMATION All current MINI engines incorporate a pressure-controlled crankcase ventilation system. The crankcase ventilation systems use various different crankcase ventilation valves, depending on the engine type. Although the valves all look different, they function similarly, using a spring and diaphragm assembly to control the crankcase pressure. A properly functioning pressure control valve is designed to maintain a slight vacuum (underpressure) in the crankcase, which assures reliable crankcase venting during all engine operating conditions. Some of the causes and results of a malfunctioning crankcase ventilation system are listed below. Causes of Excessive Overpressure (Pressure) ? Internal engine damage/wear ? Obstruction in the crankcase ventilation system ? Defective pressure control valve Results of Excessive Overpressure ? Damage to the engine oil seals ? Increased engine oil consumption (can be misdiagnosed as a defective turbocharger) ? Excessive engine oil in the intake system ? Excessive engine oil in the charged intake tubes or the intercooler on turbocharged engines (can be misdiagnosed as a defective turbocharger) ? Engine oil dip stick is dislodged from the guide tube (if equipped) Cause of Excessive Underpressure (Vacuum) ? Defective pressure control valve Results of Excessive Underpressure ? Damage to the engine oil seals ? Increased engine oil consumption ? Excessive engine oil in the intake system ? Rough engine idling or engine misfire ? Whistling or howling noise from the engine (can be misdiagnosed as a defective turbocharger)","document":{"url":"https://static.nhtsa.gov/odi/tsbs/2015/MC-10147696-9999.pdf","alternate_url":"https://static.nhtsa.gov/odi/tsbs/2015/MC-10147696-0001.pdf","confirmed":false},"url":"https://open.wenmarpro.com/bulletins/10147696","components":[{"id":"engine","name":"Engine","parent":null},{"id":"exhaust-emissions","name":"Exhaust and emissions","parent":null},{"id":"pcv","name":"Crankcase ventilation (PCV)","parent":"exhaust-emissions"}],"codes":[],"topics":[],"vehicles":[{"make":"BMW","model":"BMW","year_from":null,"year_to":null,"match":null,"vehicle_ids":[]}],"as_of":"2026-10-19","note":"A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.","attribution":[]}