Oil Separation & Breather System for BMW 3 Series E46 (1999-2005)

Clear BMW chassis

Please ensure your correct model is selected

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.

Sub-Categories

Sort By:

Turner S54 CSL Silicone Crankcase Vent Hose - E46 M3 Z3M
10X Entries Into Our F80 M3 Sweepstakes
Turner Motorsport - Corporate Logo
T#:10681673
Part#: 018562LA02
In Stock
Sale - Save 25% $ 93.99

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

$ 70.49 USD
Free Shipping on orders $49 and up
Sale - Save 25%
$ 93.99

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

$ 70.49 USD
Free Shipping on orders $49 and up

The factory rubber/plastic hoses become brittle and crack over time. Brittle and cracked hoses can cause multiple vacuum leaks that are impossible to repair without hose replacement. Vacuum leaks can cause many problems including rough running, missing, stalling at idle, and even a no-start condition.

The factory hoses offered through BMW are plastic and will yield the same results of becoming brittle and damaged over time. Our solution is a premium replacement that will outlast everyone of the OEM replacements. Our Silicone Crankcase Vent Hose can be used to replace the factory brittle hose to ensure your S54 is free from vacuum leaks and performing properly.

CSL Vent Hose (11157833649) - Silicone Crankcase Vent hose is a direct replacement

Key benefits:

Lifetime replacement of the brittle OEM plastic crankcase breather hose that is susceptible to cracking overtime from constant heat cycling

Design:

Retains OEM hose end fittings to ensure proper seal

“Black” 3 ply reinforced silicone w/ “White” Turner logo

Show More Show Less
Turner Motorsport - Corporate Logo
T#:7196695
Part#: 018562LA01
In Stock
Sale - Save 25% $ 41.99

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

$ 31.49 USD
Free Shipping on orders $49 and up
Sale - Save 25%
$ 41.99

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

$ 31.49 USD
Free Shipping on orders $49 and up
The factory rubber/plastic hoses become brittle and crack over time. Brittle and cracked hoses can cause multiple vacuum leaks that are impossible to repair without hose replacement. Vacuum leaks can cause many problems including rough running, missing, stalling at idle, and even a no-start condition. Replace the brittle or broken line that attaches between the oil separator and air box. Our Turner Silicone Crankcase Hose can be used in place of both the standard and CSL intake boxes.

Our engineers at Turner sought out to solve the degrading issues that happens with the factory crankcase vent hose and found the best solution is a silicone replacement. Our Turner Silicone Crankcase Vent Hose can be used to replace the factory brittle hose to prevent vacuum leaks and lackluster performance. Simply take your factory crankcase vent hose and remove the ends; the factory ends can be installed on the new Silicone Vent Hose with the supplied clamps for a tight seal.

Turner Silicone Crankcase Vent Hose replaces the following part #'s:

CSL Vent Hose (11157833649) - Silicone Crankcase Vent hose is a direct replacement
Non-CSL Vent Hose(11157831311) - Silicone hose will make a "U" bend with direct fitment and can also be trimmed for your own preferable fit.

- Key benefits:

Lifetime replacement of the brittle OEM plastic crankcase breather hose that is susceptible to cracking overtime from constant heat cycling
- Design:

Turner logo forward facing when hood is open
Retains OEM hose end fittings to ensure proper seal and reduce cost
“Black” 3 ply reinforced silicone w/ “White” Turner logo
includes 2 German style 430 stainless worm-drive clamps for installation
- Special care instructions:

Do not overtighten hose clamps, hand tight is recommended.
Carefully cut the OEM plastic casing from both plastic fittings for reuse

Show More Show Less
Comprehensive Constant Pressure Valve Replacement Kit
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:557341
Part#: 11111318185TMSKT
In Stock
Sale - Save 2% $ 85.93

This product was last offered at the strikethrough price on
05-03-2026

$ 84.32 USD
Free Shipping
Sale - Save 2%
$ 85.93

This product was last offered at the strikethrough price on
05-03-2026

$ 84.32 USD
Free Shipping

When your CPV O-ring fails it causes a slow oil leak on the passenger side of the engine, making an oily mess that frequently resembles a rear main seal leak. Replacing the CPV with an upgraded o-ring ensures a long-term solution to this common problem. 

The factory o-ring over time fails from heat cycling and oil exposure due to the Buna rubber used in OEM o-rings, while the included Viton Fluoroelastomer is resistant to a much higher temperature to ensure prolonged life without leaking. 

Show More Show Less

Bremmen Parts - Corporate Logo
T#:2528129
Part#: 11617533400S1
In Stock
Sale - Save 14% $ 110.99

This product was last offered at the strikethrough price on
05-03-2026

$ 94.99 USD
Free Shipping on orders $49 and up
Sale - Save 14%
$ 110.99

This product was last offered at the strikethrough price on
05-03-2026

$ 94.99 USD
Free Shipping on orders $49 and up
BMW has an ongoing issue with oil separators freezing in cold weather if driving is done before the vehicle is fully warmed up. There is often a howling noise followed by numerous oil leaks. The crankcase breather valve is used to purge the oil vapor from the engine block into the valve cover. However, sometimes condensation can cause it to freeze, causing the entire oil separator system to fail, crack, and disintegrate. Replace all the components of the oil separator system together to prevent damage to all the aspects of your engine. As long as you have everything off, you can rest assured that new parts will last and be reliable. Don't forget to order a valve cover gasket, throttle body gasket, and a new intake boot to make your separator change easier and more comprehensive.
Show More Show Less

Crankcase Vent Hose
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:30629661
Part#: 11157831311
In Stock
Sale - Save 21% $ 30.99

This product was last offered at the strikethrough price on
05-03-2026

$ 24.47 USD
Free Shipping on orders $49 and up
Sale - Save 21%
$ 30.99

This product was last offered at the strikethrough price on
05-03-2026

$ 24.47 USD
Free Shipping on orders $49 and up
Bremmen Oil Separator Kit - Level 1 - E39 E46 E83 Z3 Z4
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:641646
Part#: 11617501566S1
Ships on Oct 13, 2026
Sale - Save 15% $ 95.99

This product was last offered at the strikethrough price on
05-03-2026

$ 81.59 USD
Free Shipping
Sale - Save 15%
$ 95.99

This product was last offered at the strikethrough price on
05-03-2026

$ 81.59 USD
Free Shipping
BMW has an ongoing issue with oil separators freezing in cold weather if driving is done before the vehicle is fully warmed up. There is often a howling noise followed by numerous oil leaks. The crankcase breather valve is used to purge the oil vapor from the engine block into the valve cover. However, sometimes condensation can cause it to freeze, causing the entire oil separator system to fail, crack, and disintegrate. Replace all the components of the oil separator system together to prevent damage to all the aspects of your engine. Level 1 kit includes the following; Oil separator Hose from oil separator to dipstick tube Hose from oil separator to valve cover Hose from intake manifold back to the connector hose Hose from oil separator up to the intake manifold
Show More Show Less

Bav Auto Crankcase Pressure Regulator Valve - BMW M52 M54
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:640207
Part#: 11617501566
In Stock
Sale - Save 20% $ 32.99

This product was last offered at the strikethrough price on
05-03-2026

$ 26.39 USD
Free Shipping on orders $49 and up
Sale - Save 20%
$ 32.99

This product was last offered at the strikethrough price on
05-03-2026

$ 26.39 USD
Free Shipping on orders $49 and up
BMW has an ongoing issue with oil separators freezing in cold weather if driving is done before the vehicle is fully warmed up. There is often a howling noise followed by numerous oil leaks. The crankcase breather valve is used to purge the oil vapor from the engine block into the valve cover. However, sometimes condensation can cause it to freeze, causing the entire oil separator system to fail, crack, and disintegrate. Replace this and all the other components of the oil separator system to prevent damage to all the aspects of your engine. As long as you have everything off, you can rest assured that new parts will last and be reliable. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
Show More Show Less
Bav Auto Crankcase Ventilation Return Hose - E46 E39 E60 Z3
For vehicles with production date from 01/2000
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:638072
Part#: 11617504536
In Stock
Sale - Save 20% $ 26.99

This product was last offered at the strikethrough price on
05-03-2026

$ 21.59 USD
Free Shipping on orders $49 and up
Sale - Save 20%
$ 26.99

This product was last offered at the strikethrough price on
05-03-2026

$ 21.59 USD
Free Shipping on orders $49 and up
This is the BMW crankcase return line that goes from the intake manifold to the top CCV connecting hose. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
Show More Show Less

Packaged by Turner - Corporate Logo
T#:24344785
Part#: M54OILSEPKT
In Stock
Sale - Save 23% $ 173.99

This product was last offered at the strikethrough price on
05-03-2026

$ 133.16 USD
Free Shipping on orders $49 and up
Sale - Save 23%
$ 173.99

This product was last offered at the strikethrough price on
05-03-2026

$ 133.16 USD
Free Shipping on orders $49 and up
If you need to perform a complete oil separator system service, this Level 2 kit provides you with all of the main components necessary to service your engine oil separator system. This Level 2 kit includes the following: Oil Separator Hose from oil separator to dipstick tube Hose from oil separator to valve cover Hose from intake manifold back to the connector hose Hose from oil separator up to the intake manifold Throttle body gasket Throttle body inlet boot ICV rubber grommet Oil dipstick tube o-ring seal It is highly recommended to replace the oil dipstick tube with the updated design by BMW as this also a common place for sludge to build up.
Show More Show Less

ECS Tuning Baffled Oil Catch Can - 8oz
10X Entries Into Our F80 M3 Sweepstakes
ECS - Corporate Logo
T#:13496655
Part#: 003779ECS05-02
In Stock
Sale - Save 10% $ 238.99

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

$ 215.09 USD
Free Shipping on orders $49 and up
Sale - Save 10%
$ 238.99

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

$ 215.09 USD
Free Shipping on orders $49 and up
Upgrade Your BMW with ECS Baffled Oil Catch Can

Modern emission regulations require a closed PCV/Breather system for cleaner operation. However, inefficient oil particle capture can lead to excessive oil vapor ingestion, causing carbon buildup, reduced performance, and fuel economy. ECS Tuning's updated ECS Baffled Oil Catch Can, now with an easy-to-empty 1/4" drain fitting, is engineered to collect toxic blow-by gases, minimize carbon deposits, and reduce oil contamination within engine oil. Recirculating oil vapor ensures emissions compliance without venting to the atmosphere.

  • Key Features:
  • Highly Efficient Oil Separator: Strategically positioned 4 chamber baffle system maximizes oil/air separation and minimizes oil droplets in the intake tract.
  • Integrated Dipstick: Knurled and black anodized oil dipstick simplifies oil volume inspection.
  • Reservoir: Available in 6oz or 8oz capacity with a 1/4" NPT drain plug fitting.
  • Serviceable: Easily removable baffle plates and drain plug for cleaning.
  • Easy/Customizable Installation: Combine with the ECS Universal Bracket Kit for simplified installation and adjustable mounting locations.
  • Leak-Free Fittings: Machined -10AN ORB (O-Ring Boss) fittings available for secure connections (fittings sold separately).
Show More Show Less
Crankcase Ventilation Hose
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:30629689
Part#: 11157532649
In Stock
Sale - Save 24% $ 15.99

This product was last offered at the strikethrough price on
05-03-2026

$ 12.23 USD
Free Shipping on orders $49 and up
Sale - Save 24%
$ 15.99

This product was last offered at the strikethrough price on
05-03-2026

$ 12.23 USD
Free Shipping on orders $49 and up
Oil Separator Hose - E46, Z4
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:579880
Part#: 55080
In Stock
Sale - Save 20% $ 24.99

This product was last offered at the strikethrough price on
05-03-2026

$ 19.99 USD
Free Shipping on orders $49 and up
Sale - Save 20%
$ 24.99

This product was last offered at the strikethrough price on
05-03-2026

$ 19.99 USD
Free Shipping on orders $49 and up
Cold climate version for extra insulation! Fits all E46 and Z4 chassis equipped with an M54 engine.


Bav Auto Upper Oil Separator Vent Tube - E36 E46 E60 E84 Z3 Z4 M54 M5...
For vehicles with production date from 01/2000
10X Entries Into Our F80 M3 Sweepstakes
Bavarian Autosport - Corporate Logo
T#:640502
Part#: 11617504535
In Stock
Sale - Save 20% $ 24.99

This product was last offered at the strikethrough price on
05-03-2026

$ 19.99 USD
Free Shipping on orders $49 and up
Sale - Save 20%
$ 24.99

This product was last offered at the strikethrough price on
05-03-2026

$ 19.99 USD
Free Shipping on orders $49 and up
Runs from the top of the oil separator up to rear of the intake manifold. From 1974 to 2019, Bavarian Autosport was one of the premier vendors for BMW and MINI auto parts. We are happy to preserve the Bav Auto legacy by continuing to carry their high-quality products into the future. All Bav Auto parts will remain unchanged in design and sourced from the same OEM suppliers to ensure long-lasting reliability. We trust these parts, accessories, and upgrades so confidently that we back every Bavarian Autosport branded component with a 2-year warranty.
Show More Show Less
Oil Separator Kit - Level 1
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:15710823
Part#: E46M5411_61KT
In Stock
Sale - Save 24% $ 123.99

This product was last offered at the strikethrough price on
05-03-2026

$ 93.71 USD
Free Shipping on orders $49 and up
Sale - Save 24%
$ 123.99

This product was last offered at the strikethrough price on
05-03-2026

$ 93.71 USD
Free Shipping on orders $49 and up
Replace all the components of the oil separator system together to prevent damage to all the aspects of your engine. As long as you have everything off, you can rest assured that new parts will last and be reliable. BMW has an ongoing issue with oil separators freezing in cold weather if driving is done before the vehicle is fully warmed up. There is often a howling noise followed by numerous oil leaks. The crankcase breather valve is used to purge the oil vapor from the engine block into the valve cover. However, sometimes condensation can cause it to freeze, causing the entire oil separator system to fail, crack, and disintegrate. ur Level 1 kit includes the following; Oil separator Hose from oil separator to dipstick tube Hose from oil separator to valve cover Hose from intake manifold back to the connector hose Hose from oil separator up to the intake manifold
Show More Show Less
Bremmen Crankcase Ventilation Hose - E39 E53 E60 E83 E46
10X Entries Into Our F80 M3 Sweepstakes
Bremmen Parts - Corporate Logo
T#:640147
Part#: 11611432559
In Stock
Sale - Save 22% $ 23.99

This product was last offered at the strikethrough price on
05-03-2026

$ 18.76 USD
Free Shipping on orders $49 and up
Sale - Save 22%
$ 23.99

This product was last offered at the strikethrough price on
05-03-2026

$ 18.76 USD
Free Shipping on orders $49 and up
Crankcase Vent Hose - From Valve Cover to Oil Separator - Fit BMWs with the M52 or M54 6 cylinder engine

Cold Climate Oil Separator Kit - Level 2
10X Entries Into Our F80 M3 Sweepstakes
Packaged by Turner - Corporate Logo
T#:15744065
Part#: 114317400450-KT
In Stock
Sale - Save 41% $ 231.99

This product was last offered at the strikethrough price on
06-15-2026

$ 137.46 USD
Free Shipping on orders $49 and up
Sale - Save 41%
$ 231.99

This product was last offered at the strikethrough price on
06-15-2026

$ 137.46 USD
Free Shipping on orders $49 and up
If you are ready to perform a truly complete oil separator system service, our Level 2 kit provides you with all of our Level 1 kit components plus a throttle body gasket, throttle body inlet boot, ICV grommet, and dipstick tube o-ring. Our Level 2 Cold Climate kit includes the following: Oil separator - BMW cold climate recommended Hose from oil separator to dipstick tube - BMW cold climate recommended Hose from oil separator to valve cover Hose from intake manifold back to the connector hose Hose from oil separator up to the intake manifold Throttle body gasket Throttle body inlet boot ICV rubber grommet Oil dipstick tube o-ring seal It is highly recommended to replace the oil dipstick tube with the updated design by BMW as this also a common place for sludge to build up.
Show More Show Less

Genuine BMW - Corporate Logo
T#:32270
Part#: 11157513756
Ships in 1 day
Sale - Save 16% $ 177.99

MSRP stands for Manufacturer's Suggested Retail Price. This is the suggested retail price provided by the manufacturer, supplier or seller.

$ 148.91 USD
Free Shipping on orders $49 and up
Sale - Save 16%
$ 177.99

This product was last offered at the strikethrough price on
05-14-2026

$ 148.91 USD
Free Shipping on orders $49 and up


Genuine BMW Vent Hose -
This item fits the following BMW Chassis:
E46

Fits BMW Engines including:
M56