This BMW has a failed crankcase vent valve. Also known as the oil separator, CCV. This failure has created a high vacuum situation which is causing an engine BTW DISA valve replacement takes about 10mins. it's 1 connector and 2 bolts. also DISA failure is obvious from just listening to the engine. it makes a aweful racket. with the hood up standing on the driver side you should be able to hear it rattling if it's bad. #7 in the diagram: cost is about $170+tax+shipping. Kit contains the following parts. Part# 11617501566 Crankcase Vent Valve By OEM. Part# 11157532649 Vent Valve to Oil Dip Stick Tube By CRP-Rein OEM. Part# 11611432559 Vent Valve to Valve Cover By CRP-Rein OEM. Part# 11617504535 Connecting Hose from Vent Valve By CRP-Rein OEM. Part# 11617504536 Return Pipe from Connecting Hose By Febi-Rein OEM. With the engine idling, disconnect the vacuum hose from the M56 valve cover, and test if the hose is sucking air. That should be immediately obvious as the hose is now directly connected to the intake manifold without any sort of reducer in between. If not obvious, try using a plastic bag on the hose to see if there is vacuum at all. 2/22/23 10:45 a.m. Having just been through this with a 530, if the valve cover is leaking it's probably cracked. Old engine was cracked, replacement engine with 118k miles was also cracked. Both were cracked on the exhaust side, near the back. DISA valve and CCV valve and hoses are a must. HOW TO KNOW IF DISA VALVE IS BAD BMW E46 E39 E60 E83 Z3 Z4 E65If you have BMW and you are trying to see if you have bad DISA valve in this video we will expl Search YouTube for Scotty Smoke Test. Do what Scotty does or build a tester from related video. Remove the oil fill cap and make sure the crankcase fills up with smoke, put the oil fill cap back on and check for leaks around the valve cover, oil fill cap, dipstick tube and CCV hoses. Cracked valve covers are pretty common on the E46 as it ages. Cold-weather CCV is another engineering failure. Avoid short trips (less than 7 miles) and you will be fine. Once or twice a month, group all trips together (grocery, dry cleaner etc. etc.) and once in a while go on the highway and give your car an Italian tune-up to avoid CCV blockage. Italian tune-up. I'm good at that. Join us in today’s episode as we discuss BMW’s Crank Case Ventilation System and the issues it can cause.This is something we want to address as we see quest 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 DpvdfR.