Oil Separators & Vent lines
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche Boxster 987 MKII 2.9L 2009-2012
- Porsche Boxster S 987 MKII 3.4L 2009-2012
- Porsche Boxster 981 2.7L 2012-16
- Porsche Boxster 981 S / GTS 3.4L 2012-16


(2 per car)
Fits:
Porsche 986 Boxster 1997-05
Porsche 987 Boxster 2.7L / 3.2L 2005-06
Porsche 996 C2 / C4 / C4S 1998-05
Porsche 997 Carrera 3.6L / 3.8L 2005-08
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Diagram ref no 4
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610708054
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche 996 C2 3.4L 1997-08/01
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C2 3.6L 09/01-2005
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 C4S 3.6L 09/01-2005
- Porsche 997 MK1 Carrera 2 3.6L 2005-08
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08

Fits:
Porsche 987 Boxster 2.7L / 3.2L 2005-08
Porsche 987C Cayman 2.7L / 3.4L 2006-08
Click pictrue for large parts diagram.
Diagram Ref No 5.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
98710714500
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08

Fits:
Porsche 987 Boxster 2.7L - 2005 to 2006
Porsche 987 Boxster S 3.2L - 2006 to 2006
Engine Codes - M96.25 and M96.26
Click picture for large parts diagram.
Diagram Ref No 5.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
98710714602
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08
Fits:
Porsche 987 Boxster 2.7L - 2005 to 2006
Porsche 987 Boxster S 3.2L - 2006 to 2006
Engine Codes - M96.25 and M96.26
Diagram Ref No 5.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
98710714602
The product you are viewing cross references to these numbers
- Porsche Boxster 987 2.7L 2005 -08/08
- Porsche Boxster 987 S 3.2/3.4L 2005-08/08

Sold each - 2 required per car

Fits:
Porsche 987.2 Boxster / Cayman - 2009 to 2019
Porsche 987.2 Boxster S / Cayman S - 2009 to 2012
Porsche 981 Boxster / Cayman - 2013 to 2016
Porsche 981 Boxster S / Cayman S - 2013 to 2016
Porsche 981 Cayman GT4 - 2016
Porsche 997.2 Carrera 2 / Carrera 4 - 2009 to 2012
Porsche 997.2 Carrera 2S / Carrera 4S - 2009 to 2012
Porsche 997.2 turbo - 2009 to 2012
Porsche 991.1 Carrera 2 / Carrera 2S - 2012 to 2016
Porsche 991.1 Carrera 4 / Carrera 4S - 2012 to 2016
Porsche 991 turbo - 2012 to 2019
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Diagram ref no 12
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99970765140
The product you are viewing cross references to these numbers
- Porsche Boxster 987 MKII 2.9L 2009-2012
- Porsche Boxster S 987 MKII 3.4L 2009-2012
- Porsche Boxster 981 2.7L 2012-16
- Porsche Boxster 981 S / GTS 3.4L 2012-16
- Porsche 997 MKII Carrera C2 3.6L 2009-12
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C2S 3.8L 2009-12
- Porsche 997 MKII Carrera C4S 3.8L 2009-12
- Porsche 997 MKII Turbo 2010-13
- Porsche 991.1 Carrera C2 3.4L (350Bhp) 2012-16
- Porsche 991.1 Carrera C2S 3.8L (400Bhp) 2012-16
- Porsche 991.1 Carrera C4 3.4L (350Bhp) 2012-16
- Porsche 991.1 Carrera C4S 3.8L (400Bhp) 2012-16
- Porsche 991.1 Turbo 3.8L (520bhp) 2014-16
- Porsche 991.1 Turbo S 3.8L (560Bhp) 2014-16
- Porsche 991.2 Turbo Coupe 3.8L (540 Bhp) 2016-19
- Porsche 991.2 Turbo S Coupe 3.8L (580 Bhp) 2016-19
- Porsche 991.2 Turbo Cabriolet 3.8L (540 Bhp) 2016-19
- Porsche 991.2 Turbo S Cabriolet 3.8L (580 Bhp) 2016-19
- Porsche Cayman 2.9L 987C MKII 2009-12
- Porsche Cayman S / R 3.4L 987C MKII 2009-12
- Porsche Cayman 2.7L 981 2013-16
- Porsche Cayman S / GTS 3.4L 981 2013-16
- Porsche Cayman GT4 3.8L 2015-16


Fits:
Porsche 986 Boxster - 1997 to 2004
Porsche 996 - 1997 to 2005
Porsche 996 turbo - 2000 to 5005
Click 'Zoom in' for large parts diagram.
Diagram ref no 9
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99660521301
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche 996 C2 3.4L 1997-08/01
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C2 3.6L 09/01-2005
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 C4S 3.6L 09/01-2005
- Porsche 996 TURBO 2000-05

Fits:
Porsche 986 Boxster - 1997 to 2004
Porsche 996 - 1997 to 2005
Porsche 996 turbo - 2000 to 2005
- Guaranteed fitment
- Helps prevent harmful fuel vapors from escaping into the atmosphere
- Failing Vapor Canister Purge Valve can create a vacuum leak and cause rough idle.
- Helps restore proper air to fuel ratio for optimal gas mileage.
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Diagram ref no 9
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99660521301
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche 996 C2 3.4L 1997-08/01
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C2 3.6L 09/01-2005
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 C4S 3.6L 09/01-2005
- Porsche 996 TURBO 2000-05


Fits:
Porsche 986 Boxster - 1997 to 2004
Porsche 996 - 1997 to 2001
Click 'Zoom in' for large parts diagram.
Diagram ref no 2
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610712200
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche 996 C2 3.4L 1997-08/01
- Porsche 996 C4 3.4L 1997-08/01


Fits:
Porsche 986 Boxster 1997-04
Porsche 996 1998-05
Porsche 996 Turbo 2001-05
Porsche 996 GT3 1999-05
Click 'Zoom in' for large parts diagram.
Diagram ref no 3
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99620125509
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster 986 2.7L 1999-02
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche 996 C2 3.4L 1997-08/01
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C2 3.6L 09/01-2005
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 C4S 3.6L 09/01-2005
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche 996 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>
- Porsche 996 GT3 RS 2003-04
Oil Separators & Vent Lines – Maintain Clean Airflow and Engine Efficiency
The oil separator and vent line system plays a critical role in your Porsche’s crankcase ventilation process. By separating oil vapour from the engine’s blow-by gases, these components ensure only clean air is returned to the intake system — reducing emissions, preventing carbon build-up, and maintaining consistent engine performance.
At Design911, we stock a complete range of oil separators, breather hoses, and vent lines designed for Porsche engines of all generations. Manufactured from high-grade, heat- and oil-resistant materials, these components are built to handle the demands of high-performance driving, ensuring a tight seal, proper ventilation, and long-lasting reliability.
Whether you’re maintaining a daily-driven 911 or servicing a track-ready Cayman, our oil separators and vent lines help preserve your engine’s efficiency, longevity, and power output.
What Do Oil Separators & Vent Lines Do?
The oil separator and vent system controls crankcase pressure and removes oil vapour from the air circulating inside the engine.
Core Functions:
- Separate oil vapour from crankcase gases, keeping intake air clean.
- Prevent oil from entering the intake manifold or combustion chamber.
- Maintain stable crankcase pressure for efficient engine breathing.
- Reduce harmful emissions and extend engine life.
- Support consistent power delivery and smooth idle performance.
By ensuring clean ventilation and stable pressure, these components protect your Porsche’s engine from oil contamination and performance loss.
Why Do Oil Separators & Vent Lines Fail?
Over time, heat cycles, oil vapours, and pressure fluctuations cause these parts to degrade or clog, leading to poor ventilation and increased oil consumption.
- Common Causes of Failure Include:
- Clogged internal membranes in the separator.
- Cracked or brittle vent lines from heat and age.
- Oil leaks from worn seals or connections.
- Vacuum leaks, causing rough idling or poor throttle response.
- Build-up of sludge or condensation within breather hoses.
Typical symptoms include increased oil consumption, blue exhaust smoke, rough idle, or oil leaks around the intake area, all indicating the need for inspection or replacement.
Why Replace Components?
Replacing a faulty oil separator or vent line restores proper crankcase ventilation and prevents costly engine issues like carbon build-up or oil contamination. Our precision-engineered replacements are designed for accurate fitment and long-term durability, ensuring your Porsche operates efficiently.
Key Benefits:
- Restores clean airflow and stable crankcase pressure.
- Reduces oil leaks and smoke from the exhaust.
- Improves fuel efficiency and throttle response.
- Constructed from high-quality, heat- and oil-resistant materials.
- Direct-fit compatibility with Porsche engines.
- Ideal for maintenance, rebuilds, or performance tuning.
Upgrading or replacing your oil separator and vent lines is essential for maintaining your Porsche’s smooth performance and clean emissions system.
Highlights:
- High-quality Porsche oil separators, breather hoses, and vent lines.
- Ensures clean crankcase ventilation and stable engine pressure.
- Reduces oil leaks, smoke, and carbon build-up.
- Durable construction for long-term reliability.
- Direct-fit for Porsche 911, Cayman, Boxster, Panamera & more.
- Perfect for preventive maintenance or full engine rebuilds.