Emissions System for BMW 3 Series E46 (1999-2005)

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Is your BMW throwing emissions related codes? While we're primarily a BMW performance parts house, we understand the importance of maintaining your emissions system to pass inspection in your area and keep your check engine light off. Pick up your emissions related parts from Turner Motorsport.

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Bremmen Oil Separator Kit - Level 1 - E39 E46 E83 Z3 Z4
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Bremmen Parts - Corporate Logo
T#:641646
Part#: 11617501566S1
In Stock
Sale - Save 30% $ 97.99

This product was last offered at the strikethrough price on
11-07-2026

$ 68.59 USD
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Sale - Save 30%
$ 97.99

This product was last offered at the strikethrough price on
11-07-2026

$ 68.59 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
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URO PCV Breather Hose Kit - E39, E46, E83
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URO - Corporate Logo
T#:592719
Part#: BMM54PCVKIT
In Stock
$ 117.99 USD
Free Shipping
$ 117.99 USD
Free Shipping
Comes with everything needed to refresh the PCV System!
ECS Baffled Oil Catch Can System - E46 M3
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ECS - Corporate Logo
T#:394194
Part#: 015515ECS01-01KT
Ships on Mar 31, 2027
Sale - Save 20% $ 489.99

This product was last offered at the strikethrough price on
11-07-2026

$ 391.99 USD
Free Shipping
Sale - Save 20%
$ 489.99

This product was last offered at the strikethrough price on
11-07-2026

$ 391.99 USD
Free Shipping

Modern day emissions regulations require the use of a closed crankcase ventilation (PCV) system to recirculate combustion blow-by gases from the crankcase back in to the intake to be burned.  Unfortunately, these blow by gases contain water vapor (which is a byproduct of combustion) and pick up oil mist from and the windage cloud and cam lubrication system as they travel through the crank case.  Due to less than 100% effective air/oil separation in the stock PCV system, some oil mist and water vapor gets carried back to the intake tract and over time cause oil deposits in the intake manifold, intake ports, and on the back of intake valves.  All will eventually lead to poor performance and reduced fuel economy, and the presence of this oil mist in the intake charge may even increase the risk of engine-damaging detonation. 

With forced induction, track use, and/or extended high RPM usage, these symptoms increase as the factory PCV system is overwhelmed, and a catch can becomes a must for your E46 M3. This kit is a direct fit making this an easy reversal if desired as well as maintaining a clean appearance by utilizing the open "smuggler's compartment" on the passenger side of the engine bay.

ECS engineers developed a catch can that utilizes a strategically designed 4 chamber baffle plate system engineered to create multiple changes in the direction of airflow to cause oil droplets to fall out of suspension, maximizing the efficiency of the PCV air/oil separation.  A dipstick is integrated into the cap so you can monitor the oil level, and the can is easily serviced.  At each oil change simply unscrew the canister and empty the trapped oil with your regular used oil.  The ECS Oil Catch Can is CNC machined from billet 6061-T6 aluminum and with a stealthy black anodized finish for lasting durability and appearance, and includes everything needed for an OEM-like fully reversible installation.  

The ECS Oil Catch Can is made from aluminum and with a stealthy black anodized finish. The location is key as heat will evaporate the oil and send too much vapor back into the engine (where cooler air will turn it back into fluid). The ECS OCC also has a factory-like appearance. Having a kit designed specifically for your E46 M3 makes for a clean looking setup that any skill level mechanic can install. 

Note: Since the crankcase vent system is considered part of the overall emissions system, installing this may be a violation of local, state, and federal laws. While exemptions are made for track/race and off-road use, check with your local state inspection facility on using this in street-driven vehicles.

*Click here for installation instructions*

ECS Oil Catch Can Features:
+ Increases air intake efficiency
+ Promotes engine longevity
+ 4 chamber design promotes excellent air/oil separation
+ Large In/Out ports (no tapered sizes that slow flow)
+ Anodized black lightweight aluminum
+ Made in USA

This item fits the following BMWs
E46 M3 2001-2006

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"Cold Climate" Oil Separator Kit
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URO - Corporate Logo
T#:377838
Part#: 11617534237
Ships in 1 Business Day
$ 74.99 USD
Free Shipping
$ 74.99 USD
Free Shipping
URO Parts is one of the leading manufacturers of high quality direct replacement aftermarket components, covering a wide range of makes and models. All of their replacement parts are manufactured to ISO 9000 certification standards, so you can expect long lasting performance from URO Parts.
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"Cold Climate" Crankcase Pressure Regulator Valve
Superior performance for both warm and cold climates
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URO - Corporate Logo
T#:376770
Part#: 11617533400
Ships in 1 Business Day
$ 40.99 USD
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$ 40.99 USD
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Commonly referred to as the "oil separator" or PCV