Oil Separators & Vent lines

Sold individually; x2 required per vehicle.
Fits:
Porsche 997-1 Carrera S 2005-08
Porsche 997-1 Carrera 4S 2006-08
Porsche 997-1 Targa 4S 2007-08
Diagram ref. 10.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710753800
The product you are viewing cross references to these numbers
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08


Fits:
Porsche 911 - 1978 to 1989
Porsche 964 - 1989 to 1994
Porsche 993 - 1994 to 1998
Porsche 986 Boxster - 1997 to 2004
Porsche 996 - 1997 to 2005
Porsche 997.1 - 2005 to 2008
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99951255400
The product you are viewing cross references to these numbers
- Porsche Boxster 986 2.5L 1997-99
- Porsche Boxster S 986 3.2L 1999-02
- Porsche Boxster 986 2.7L 2003-04
- Porsche Boxster S 986 3.2L 2003-04
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
- Porsche 964 (911) TURBO 3.3L 1991-93
- Porsche 964 (911) TURBO 3.6L 1991-93
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97
- 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
- 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
- Porsche 997 MK1 TURBO 2007-09
- Porsche 997 MK1 GT3 2007-09
- Porsche 997 MK1 GT2 2007-09


Fits:
Porsche 987 Boxster 2.7L / 3.2L 2005-08
Porsche 987C Cayman 2.7L / 3.4L 2005-08
Porsche 996 Carrera 3.6L 2003-05 (M96.03)
Porsche 997 Carrera 3.6L 2005-08 COUPE / CABRIO (M96.05)
Click 'Zoom in' for large parts diagram.
Diagram Ref No 10.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610717550
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 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 4 3.6L 2005-08
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
Fits:
Porsche 987 Boxster 2.7L / 3.2L 2005-08
Porsche 987C Cayman 2.7L / 3.4L 2005-08
Porsche 996 Carrera 3.6L 2003-05 (M96.03)
Porsche 997 Carrera 3.6L 2005-08 COUPE / CABRIO (M96.05)
Diagram Ref No 10.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610717550
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 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 4 3.6L 2005-08
- Porsche Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
2 Required per car Left or Right, Price is each

Fits:
Porsche 997 3.8L Carrera 2S / 4S 2005-08
Click picture for large parts diagram.
Diagram Ref No 9. Left or Right
Price is for each.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710713800
The product you are viewing cross references to these numbers
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08

2 Required per car Left or Right, Price is each

Fits:
Porsche 997 3.8L Carrera 2S / 4S 2005-08
Click 'Zoom in' for large parts diagram.
Diagram ref no 9.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710713800
The product you are viewing cross references to these numbers
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08


(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
Click 'Zoom in' for large parts diagram.
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

1 per car

Fits:
Porsche 997 3.8L Carrera 2S / 4S 2005-08
Click 'Zoom in' for large parts diagram.
Diagram Ref No 1.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710703801
The product you are viewing cross references to these numbers
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
Oil Separator - Main Centre unit - is a direct-fit replacement for the factory crankcase ventilation system component used on Porsche 911 (997) Carrera 3.8L 2S / 4S engines. This separator plays a vital role in maintaining crankcase pressure equilibrium by separating oil mist from blow-by gases before routing clean air back into the intake manifold.
Fits:
Porsche 997 3.8L Carrera 2S / 4S 2005 - 2008
Diagram Ref No 1.
• Function: Separates oil vapours from crankcase gases to prevent oil ingestion
• Position: Engine – main centre, crankcase ventilation housing
• Benefits: OE-style fit, improved oil vapor separation, durable diaphragm construction
• Installation: Direct-fit replacement; verify hose routing and seals during reassembly
Over time, the oil separator’s diaphragm and housing can degrade from heat cycling, oil vapour, and pressure changes, leading to vacuum leaks, oil smoke, or excessive consumption.
Replace this unit when:
• You see oil residue or smoke from the exhaust or intake
• The engine shows rough idle, whistling sounds, or high vacuum
• Oil consumption has increased significantly
• During engine service or PCV system maintenance
Replacing restores balanced crankcase pressure, prevents oil ingestion, and maintains clean combustion — ensuring your Porsche 997’s 3.8L engine performs at its best.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710703801
The product you are viewing cross references to these numbers
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08


Fits:
Porsche 997.1 Carrera 2S / 4S 3.8L
Click 'Zoom in' for large parts diagram.
Diagram ref no 14
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99710602802
The product you are viewing cross references to these numbers
- Porsche 997 MK1 Carrera 2S 3.8L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
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.