Original BMW Crankcase Breather Hose, Cylinders 1-4, for BMW 550i, 650i, 750i, X5, and X6 (2008–2014)

This Original BMW crankcase breather hose is the connecting line that carries crankcase ventilation gases for cylinders 1-4 on the N63 V8 used in the BMW 550i, 650i, 750i, Alpina B7, X5 xDrive50i, and X6. BMW names the part a connecting line and assigns it to cylinders 1 through 4, which puts it on the right cylinder bank. In a positive crankcase ventilation system, a breather hose carries pressurized crankcase air to the air/oil separator. The separator returns oil vapor to the engine and sends the remaining air to the intake to be burned. The constant mix of heat, pressure, and oil vapor makes this hose a common failure point in the system. The part weighs 103 g and is sold individually.

Original BMW Parts carry a 24-month parts warranty.

BMW put this version into production in May 2012. BMW marks it as exchangeable retrospectively with the earlier part 11-15-7-575-642, so it also replaces that number on cars built before the change. Because the N63 has two cylinder banks, check which bank your hose sits on before you order. This line serves cylinders 1-4 on the right bank only. Plastic connectors on PCV hoses become brittle with heat and oil exposure, and the securing clips can break during removal or during other engine work.

Technical Details

• Manufacturer: BMW (genuine part)
• Part number: 11-15-7-646-086
• BMW part name: connecting line, cylinders 1-4
• Position: right cylinder bank, N63 V8
• Weight: 103 g (0.2 lb)
• Production start: May 2012
• Supersedes 11-15-7-575-642, exchangeable retrospectively
• Sold individually
• Warranty: 24-month parts warranty

Common Questions

What symptoms point to a failed breather hose?
Look for cracks or splits in the hose, broken connectors, and oil residue on the hose or the parts around it. Unmetered air from a leak can set a check engine light for an intake air leak. A severe leak can cause rough running or a misfire.

My car has the older part number. Will this one fit?
Yes. BMW marks 11-15-7-646-086 as exchangeable retrospectively with 11-15-7-575-642.

Can the hose be damaged during other engine work?
Yes. The plastic clips and connectors become brittle over time and can break when the hose is disturbed.

Fitment & Compatibility

Use the table below to verify the year and submodel for your build. PMB Performance can confirm this against your VIN, backed by more than 20 years of parts and fitment work.