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Oil Separators & Vent lines

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DISPLAYING 1 to 16 (of 17 products)
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99610702602/KIT
Product Information
Product Information
AOS Oil / air separator & hose kit. One of the most common failures in the Boxster or 996 is the Air/Oil Separator, also referred to as the AOS.

Fits:
Porsche Boxster 986 2003>>
Porsche Boxster 987 2005>>
Porsche Cayman 987 2005>>

The AOS is basically a small diaphragm distillery which distills the minute amounts of oil mist in the crankcase, liquifies it and sends it back to the crankcase. The "clean" air is now sent into the air intake (after the throttle body) to be burned off by the engine.

When the AOS starts to fail it cannot separate all of the oil out of the mist and some liquid oil is sent to the air intake.

A few drops of oil is enough to generate the GREAT SMOKE BOMB for which our cars are famous for.
A big smoke bomb once in a while is completely normal, due to the architecture of the flat-6 engine, which may let a drop of oil flow into one of the combustion chambers sporadically.

Click 'Zoom in' for large parts diagram.
Diagram Ref No 1, 4, 5, 10

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99610702602
99610702601
99610702600
99610702602
996-107-026-01
98710714502
98710724601
99610717550
98710714602

The product you are viewing cross references to these numbers
AOSKIT987
Product Information
Product Information
Have you suffered from packed up oil separator? Are you worried that it will ruin your track day experience?
This twin chamber conversion kit will put your mind at ease. Porsche has developed Motorsport version of AOS to avoid future problems. Fit and forget.

porsche

Fits:
Porsche 987 Boxster
Porsche 987C Cayman

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

AOSKIT987
98710792600
98710794600
98710794700
90006731601

The product you are viewing cross references to these numbers
OILSEPKIT981
Product Information
Product Information
Oil / Air Separator kit.
This kit is the complete factory-specified breathing and oil-vapour separation system for the 981 Boxster and Cayman engines. It comprises the oil-separator unit, two vent valves, and all necessary hoses. Together, they ensure the crankcase is ventilated properly, blow-by vapours are separated, and only clean, oil-free air is recirculated or vented.

Fits:
Porsche 981 Boxster 2012 - 2016
Porsche 981 Boxster Spyder 2016>>
Porsche 982 Boxster GTS 4.0L 2017>>
Porsche 981C Cayman 2014 - 2016
Porsche 981C Cayman GT4 2016>>
Porsche 982C Cayman GT4 4.0L 2017>>

Diagram ref no 12 (
Oil separator)
Diagram ref no 1, 2, 12 and 14.

Kit Contents:
1× 0PB115099A - Air-Oil Separator (AOS) body / main separator unit
1× 9A110503801 - Crankcase Vent Valve (cylinders 4–6)
1× 9A110503900 - Crankcase Vent Valve (cylinders 1–3)
1× 9A110752020 - Crankcase Vent Hose / Breather Line
1× 9A110751501 - Additional Crankcase Breather Hose (or secondary vent line)

All parts are Genuine Porsche OEM - manufactured to original factory specifications for materials, dimensions, sealing and performance.

Recommended when replacing the AOS system, during engine maintenance, or when experiencing symptoms of AOS failure (oil consumption, smoke, vapour in intake, etc.).

Replace all components together as a kit for best sealing, balance, and long-term reliability.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

OILSEPKIT981
9A110704201
0PB115099A
9A110503800
9A110503801
9A110523800
9A110503900
9A110523902
9A110751501
9A110752020

The product you are viewing cross references to these numbers
OILSEPKIT987.2
Product Information
Product Information
Oil / Air Separator kit.
This kit is the complete factory-specified breathing and oil-vapour separation system for the 987.2 Boxster and Cayman engines. It comprises the oil-separator unit, two vent valves, and all necessary hoses. Together, they ensure the crankcase is ventilated properly, blow-by vapours are separated, and only clean, oil-free air is recirculated or vented.

Fits:
Porsche 987.2 Boxster 2009 - 2012
Porsche 987C.2 Cayman 2009 - 2012

Diagram ref no 15 (
Oil separator)
Diagram ref no 3, 4, 5 and 8

Kit Contents:
1× 0PB115099A - Air-Oil Separator (AOS) body / main separator unit
1× 9A110503801 - Crankcase Vent Valve (cylinders 4–6)
1× 9A110503900 - Crankcase Vent Valve (cylinders 1–3)
1× 9A110752002 - Crankcase Vent Hose / Breather Line
1× 9A110751501 - Additional Crankcase Breather Hose (or secondary vent line)

All parts are Genuine Porsche OEM - manufactured to original factory specifications for materials, dimensions, sealing and performance.

Recommended when replacing the AOS system, during engine maintenance, or when experiencing symptoms of AOS failure (oil consumption, smoke, vapour in intake, etc.).

Replace all components together as a kit for best sealing, balance, and long-term reliability.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

OILSEPKIT987.2
9A110704201
0PB115099A
9A110503800
9A110503801
9A110523800
9A110503900
9A110523902
9A110752001
9A110752002
9A110751501

The product you are viewing cross references to these numbers
Special Order item
0PB115099A
Product Information
Product Information
Oil / Air Separator.
The Genuine Porsche Air-Oil Separator is the factory-specified unit responsible for separating oil mist from crankcase blow-by gases on modern Porsche flat-6 engines. As part of the PCV system, it ensures clean ventilation, stable crankcase pressure, and proper oil control - critical for protecting the intake system and maintaining optimal engine performance.

Fits:
Porsche 987.2 Boxster 2009 - 2012
Porsche 981 Boxster 2012 - 2016
Porsche 981 Boxster Spyder 2016>>
Porsche 982 Boxster GTS 4.0L 2017>>
Porsche 987C.2 Cayman 2009 - 2012
Porsche 981C Cayman 2014 2016
Porsche 981C Cayman GT4 2016>>
Porsche 982C Cayman GT4 4.0L 2017>>

Diagram ref no 16

A factory-original air-oil separator designed to filter blow-by vapours, remove oil mist, and maintain stable crankcase ventilation.

Sold individually. It is recommended to also inspect and, if necessary, replace associated hoses and seals when fitting a new separator to ensure full system integrity.

This AOS:
  Removes oil droplets and vapour from crankcase gases before they enter the intake
  Maintains correct crankcase vacuum and pressure balance
  Reduces oil consumption and prevents oil contamination in the intake tract
  Helps prevent carbon build-up, fouled sensors, and smoky exhaust
  Ensures emissions compliance and proper engine breathing




Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

0PB115099A
9A110704201
9A110704200
9A110704202
0PB115099A

The product you are viewing cross references to these numbers
0PB115099A/1
Product Information
Product Information
Oil / Air Separator.
A crankcase air-oil separator (AOS) that traps oil droplets and vapour from the engine’s blow-by gases and returns cleaned air to the intake system while keeping oil inside the engine’s lubrication system.
Sold individually. It is recommended to also inspect and, if necessary, replace associated hoses and seals when fitting a new separator to ensure full system integrity.

Fits:
Porsche 987.2 Boxster 2009 - 2012
Porsche 981 Boxster 2012 - 2016
Porsche 981 Boxster Spyder 2016>>
Porsche 982 Boxster GTS 4.0L 2017>>
Porsche 987C.2 Cayman 2009 - 2012
Porsche 981C Cayman 2014 2016
Porsche 981C Cayman GT4 2016>>
Porsche 982C Cayman GT4 4.0L 2017>>

Diagram ref no 16

This air-oil separator is an replacement unit designed to filter crankcase blow-by vapours on Porsche engines, separating oil mist from the air before routing clean air back into the intake or ventilation system.

Over time AOS units degrade - internal baffles can become clogged, seals can fail, or plastic can crack due to heat cycles. A faulty or clogged separator may allow oil vapour into the intake, causing:
  Increased oil consumption and oil-soaked intake/tracks.
•  Blue or grey smoke from exhaust, rough idle, misfires or poor running.
  Sludge or carbon buildup, fouled sensors, and potential engine damage.

Replacing with a correct fresh separator restores clean crankcase ventilation, keeps oil inside, and helps maintain reliable performance and engine health.

You should replace the air-oil separator when:
 You notice oil in the intake system, oil residue around intake or throttle body, or excessive oil consumption.
 The separator is showing signs of age: cracks, hardened plastic, degraded seals, or clogging.
 Your engine exhibits excessive smoke, rough idling, or misfires potentially related to intake contamination.
 Carrying out engine maintenance, PCV servicing, or installing new hoses/seals.
 The separator hasn’t been replaced for many years or high mileage - preventive maintenance helps avoid more serious issues.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

0PB115099A
9A110704201
9A110704200
9A110704202
0PB115099A

The product you are viewing cross references to these numbers
Special Order item
99610702602
Product Information
Product Information
Oil / air separator. One of the most common failures in the Boxster or 996 is the Air/Oil Separator, also referred to as the AOS.

porsche

Fits:
Porsche Boxster 986 2003>>
Porsche Boxster 987 2005>>
Porsche Cayman 987 2005>>

The AOS is basically a small diaphragm distillery which distills the minute amounts of oil mist in the crankcase, liquifies it and sends it back to the crankcase. The "clean" air is now sent into the air intake (after the throttle body) to be burned off by the engine.

When the AOS starts to fail it cannot separate all of the oil out of the mist and some liquid oil is sent to the air intake.

A few drops of oil is enough to generate the GREAT SMOKE BOMB for which our cars are famous for.
A big smoke bomb once in a while is completely normal, due to the architecture of the flat-6 engine, which may let a drop of oil flow into one of the combustion chambers sporadically.

Click 'Zoom in' for large parts diagram.
Diagram Ref No 1.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99610702602
99610702601
99610702600
99610702602
996-107-026-01

The product you are viewing cross references to these numbers
99610702602/1
Product Information
Product Information
Oil / air separator. One of the most common failures in the Boxster or 996 is the Air/Oil Separator, also referred to as the AOS.

oematch

Fits:
Porsche Boxster 986 2003>>
Porsche Boxster 987 2005>>
Porsche Cayman 987 2005>>

The AOS is basically a small diaphragm distillery which distills the minute amounts of oil mist in the crankcase, liquifies it and sends it back to the crankcase. The "clean" air is now sent into the air intake (after the throttle body) to be burned off by the engine.

When the AOS starts to fail it cannot separate all of the oil out of the mist and some liquid oil is sent to the air intake.

A few drops of oil is enough to generate the GREAT SMOKE BOMB for which our cars are famous for.
A big smoke bomb once in a while is completely normal, due to the architecture of the flat-6 engine, which may let a drop of oil flow into one of the combustion chambers sporadically.

Click 'Zoom in' for large parts diagram.
Diagram Ref No 1.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99610702602
996-107-026-01
99610702601
99610702600
99610702602
996-107-026-01

The product you are viewing cross references to these numbers
Special Order item
99610124151
Product Information
Product Information
Crankcase oil separator gasket, 1-3 cyl.

porsche

Fits:
Porsche 986 Boxster 1997-04
Porsche 987.1 Boxster 2005-08
Porsche 987C.1 Cayman 2005-08
Porsche 996 Carrera 3.4L / 3.6L 1998-05
Porsche 997.1 Carrera 3.6L / 3.8L 2005-08

Click 'Zoom in' for large parts diagram.
Diagram ref no 20

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99610124151
99610124251
99610124151
280.300

The product you are viewing cross references to these numbers
Special Order item
99951268309
Product Information
Product Information
Oil / Air Separator Boot Clamp. 23 x 12.

porsche

Fits:
Porsche 987 Boxster 2005-08
Porsche 987C Cayman 2006-08
Porsche 996 C2 / C4 / C4S 3.6L 2002-05

Click pictrue for large parts diagram.
Diagram Ref No 9.

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

99951268309
99951268309

The product you are viewing cross references to these numbers
Special Order item
99610717550
Product Information
Product Information
Replacement oil separator boot.

porsche

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
99610717550

The product you are viewing cross references to these numbers
99610717550/1
Product Information
Product Information
Replacement oil separator boot.

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
99610717550

The product you are viewing cross references to these numbers
Special Order item
9A110702007
Product Information
Product Information
Oil conducting housing

porsche

Fits:
Porsche 987.2 Boxster / Boxster S 2009-12
Porsche 987C.2 Cayman / Cayman S  2009-12

Click 'Zoom in' for large parts diagram.
Diagram ref no. 1

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

9A110702007
9A110704601
9A110702001
9A110702003
9A110702007

The product you are viewing cross references to these numbers
Special Order item
98710792600
Product Information
Product Information

Porsche Motorsports Air Oil Separator. A must for any M96 engine that will be used on track.  Helps to reduce the amount of oil that gets into the intake manifold when tracking your Porsche Boxster, Cayman or 911 vehicle with the M96/M97 engineModifications will be required on vehicles not already fitted with a Motorsports AOS Requires Qty 2 bolt part number 90006731601 (sold separately). 

porsche

Fits:
Porsche 987.1 Boxster
Porsche 987C.1 Cayman

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

98710792600
98710792600

The product you are viewing cross references to these numbers
Special Order item
98710724601
Product Information
Product Information
Oil separator breather line, Cyl. 4-6.

porsche

Fits:
Porsche 987.1 Boxster 2005-08
Porsche 987C.1 Cayman 2006-08

Click 'Zoom in' for large parts diagram.
Diagram ref no 4

Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.

98710724601
98710724601
98710714701

The product you are viewing cross references to these numbers
Special Order item
98710714500
Product Information
Product Information
Oil Separator Pipe.

 
porsche

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
98710714500

The product you are viewing cross references to these numbers
DISPLAYING 1 to 16 (of 17 products)
1 2
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About Oil Separators & Vent lines

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.

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