Oil Separation & Breather System for BMW 4 Series F33 (2014+)

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Every car has a crankcase vent system that is supposed to suppress oil from making it into the intake ports and combustion chamber. A good functioning system will separate oil from the atmosphere and return it to the oil pan (or collect it in a catch can) while allowing the leftover vapors to burn in the combustion chamber or recirculate through the system. This has always been known as a PCV system (Positive Crankcase Ventilation) but BMW has several other names for it - oil separator, crankcase vent (CCV), and cyclonic separator. Failures in the system will allow raw oil to enter the intake and eventually into the engine itself which can have disastrous effects on engine performance and longevity. As emissions regulations on oil and gas venting have gotten more stringent the PCV systems have gotten more complex and failure prone. And because the CCV is intertwined with other systems you could experience rough running, loss of power, higher oil consumption, misfiring, stalling, or other annoying issues. There is no replacement interval for these so we recommend inspecting your crankcase vent system as part of your regular maintenance routines. Symptoms of a bad crankcase vent are: whitish or yellowish film on the underside of the oil cap, whistling/squealing noises (not caused by a belt), suction on the oil cap that makes it hard to unscrew, large amounts of white smoke from the exhaust, and excessive oil consumption.

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Upgraded Silicone PCV Hose - (11127588417) - N20/N26

affirm Starting At 0% APR - Subject To Eligibility. See Lending Terms

T#:46203566

Part#: 018501LA02

Ships on Aug 3, 2026

Sale - Save 25% $ 101.99

This product was last offered at the strikethrough price on
06-14-2026

$ 76.49 USD

Add to Wish List

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Sale - Save 25%

$ 101.99

This product was last offered at the strikethrough price on
06-14-2026

$ 76.49 USD

Add to Wish List

Due to weak plastic construction, the factory plastic crankcase ventilation breather hose is known to fail. After years of exposure to piping-hot engine bay temperatures and chemical-laden oil vapors, the corrugated plastic tubing can crack, crumble, or fail altogether.

We set out to bulletproof your N20 PCV system with a durable silicone breather hose, designed to provide a comprehensive upgrade and permanent replacement for the factory plastic hose. By replacing the flimsy, heat-hardened OEM plastic hose with a four-ply fluorosilicone hose, you'll experience peace of mind knowing your N20 is free from the inevitable return of oil leaks, vacuum leaks, and drivability concerns that would have been.

This breather hose is found at the front of the engine, and is used to connect the inlet pipe to the valve cover. It replaces OEM part number 11127588417.

Features:

Silicone construction ensures a durable replacement that is sure to outlast OE plastic
Designed as a direct replacement for the factory breather hose
Retains heating function and OE electrical connector
Design:

Four-ply wire-reinforced fluorosilicone hose is designed to resist degradation due to exposure to oil vapors
O-rings are pre-installed in OE connectors for a lasting seal
Includes pre-installed zinc-coated hose clamps for durability and corrosion resistance
Product Development:

Our Silicone PCV Hose Upgrade was designed, engineered, tested, and quality inspected by our Research and Development team in our Wadsworth, Ohio, facility. We strive for the highest level of precision and quality through leading-edge product development technology, including FARO laser scanning for reverse engineering and quality inspection, SolidWorks 3D CAD modelling, rapid prototyping utilizing our in-house 3D printer, and rigorous long-term product testing.

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Oil Separation & Breather System for BMW 4 Series F33 (2014+)

Upgraded Silicone PCV Hose - (11127588417) - N20/N26

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