Original BMW B58 Crankcase Vent Pipe to Valve Cover for BMW 2, 3, 4, 5, 6 GT, and 7 Series, X3, and X4 (2016–2021)

The Original BMW crankcase vent pipe 11-15-7-637-521 is the vent line that connects to the valve cover on the B58 six-cylinder engine in the BMW 340i, 440i, 540i, 740i, M240i, X3 M40i, and X4 M40i from 2016–2021. BMW names it simply the vent pipe and has built it since July 2015. It is part of the positive crankcase ventilation system, which carries oil vapor and blow-by gas out of the crankcase so the engine can burn it instead of venting it. Made in France, it is sold individually as a single piece. The pipe lives with constant heat, oil vapor, and crankcase pressure, and over time those conditions break down the plastic and make the connectors brittle.

Original BMW Parts carry a 24-month parts warranty.

One part number covers every B58 application in this range, so there is no separate version for xDrive, Gran Coupe, or Gran Turismo models. BMW's parts data shows it on the F22 and F23 2 Series, the facelifted F30 and F34 3 Series, the F32, F33, and F36 4 Series, the G30 5 Series, the G32 6 Series Gran Turismo, the G11 and G12 7 Series, the G01 X3, and the G02 X4. A failing vent pipe usually shows itself as oily residue on the hose and nearby engine surfaces, a check engine light for an intake air leak or airflow fault, or in severe cases rough running and a misfire.

Technical Details

• Manufacturer: BMW (Original BMW Parts)
• Part number: 11-15-7-637-521
• BMW part name: vent pipe
• System: positive crankcase ventilation, connects to the valve cover
• Engine: B58 inline six-cylinder
• Production start: July 2015
• Country of manufacture: France
• Sold as: one piece
• Warranty: 24-month parts warranty

Installation & Tuning Notes

PCV line connectors turn brittle with heat and oil exposure, and their securing clips break easily during removal or while other service work is going on nearby, so release the clips on the old pipe carefully. If heavy oil residue covers the area, degreasing it first helps pin down exactly where the vapor is escaping.

Common Questions

What can a cracked crankcase vent pipe do to the engine?
Unmetered air entering through a leak can set a check engine light for an intake air leak or other airflow-related codes. A severe leak can cause rough running and a misfire, and escaping vapor can leave a burnt oil smell.

Is the M240i xDrive pipe different from the rear-drive M240i pipe?
No. The same part number covers both the M240i and M240i xDrive from 2017–2021.

Fitment & Compatibility

Confirm your model year and submodel against the table below before ordering. PMB Performance can confirm this against your VIN, backed by more than 20 years of parts and fitment work.