do not press the back button…
Enter your VAT number here and click Verify:
Your details have been verified. VAT number registered to:
,
.
Your order will now be zero rated for VAT purposes. We reserve the right to verify these details after your order request has been made and reinstate VAT if required.
Your VAT details were not recognised or were invalid. Your VAT number must be matched to your Billing Country as specified above. This is currently specified as . You do not need to enter the country code part of your VAT number as this has already been selected in your billing address details above.
The VAT number checking service is currently offline. Please supply your VAT details within the comments or special instructions field below and we will apply a VAT discount after placing your order request.
Oil Separators & Vent lines
By OE Match
.jpg?width=197 "AOS Oil / air separator & hose kit Porsche Boxster 986 2003>> 99610702602 - 99610702601, 99610702600, 99610702602, 996-107-026-01, 98710714502, 98710724601, 99610717550, 98710714602")
- 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
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 - 2004
Porsche Boxster 987.1 2005 - 2008
Porsche Cayman 987C.1 2005 - 2008
Diagram Ref No 1, 4, 5, 10
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.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
OILSEPARATOR.986S.2.OEM
The product you are viewing cross references to these numbers
This kit is comprised of the following items:
- 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 Cayman 2.7L 987C 2006-08
- Porsche Cayman S 3.4L 987C 2005-08
Engine oil separator also known as a crankcase vent valve or AOS. It functions as part of the engine’s positive crankcase ventilation (PCV) system, managing and separating blow-by gases and oil vapour to help maintain engine performance and emissions compliance.
Fits:
Porsche Boxster 986 2003 - 2004
Porsche Boxster 987.1 2005 - 2008
Porsche Cayman 987C.1 2005 - 2008
Diagram Ref No 1.
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.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610702602
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
Also referred to as an oil separator hose or breather hose, this component plays a vital role in routing crankcase gases and oil vapours through the AOS system. This OE Match oil separator boot is a direct replacement part, manufactured to original specifications for precise fitment and long-term durability. It is installed between the air-oil separator and the crankcase, acting as a flexible connection that maintains a sealed system while accommodating engine movement.
Fits:
Porsche 987 Boxster 2.7L / 3.2L 2005 - 2008
Porsche 987C Cayman 2.7L / 3.4L 2005 - 2008
Porsche 996 Carrera 3.6L 2003 - 2005 (M96.03)
Porsche 997 Carrera 3.6L 2005 - 2008 COUPE / CABRIO (M96.05)
Diagram Ref No 10.
The boot allows crankcase gases to flow from the engine to the air-oil separator, where oil vapours are separated and returned to the engine while clean air is recirculated. If this hose fails or splits, it can lead to oil leaks, vacuum leaks, and poor engine performance.
Function
• Connects the air-oil separator to the crankcase
• Maintains sealed crankcase ventilation system
• Routes oil vapours for proper separation and recirculation
• Prevents oil leaks and vacuum loss
This component is essential for maintaining correct engine breathing and emissions performance.
Over time, the hose can become brittle, crack, or split due to heat and oil exposure. A failing hose can cause oil leaks, unmetered air entering the engine, and incorrect crankcase pressure. Replacing the boot ensures proper AOS system function, prevents oil contamination, and maintains smooth engine operation.
When to replace
• Oil leaks around engine or separator area
• Rough idle or vacuum-related issues
• Visible cracks or splits in hose
• Oil residue on engine components
• During AOS (air-oil separator) replacement
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99610717550
The product you are viewing cross references to these numbers
OEMatch Oil Separators & Vent lines — Durability, Sealing, Performance
The oil separator and vent line system manages crankcase ventilation on Porsche engines by separating oil vapour from blow-by gases and returning cleaner air to the intake. Properly functioning separators and breather hoses reduce oil contamination and help preserve throttle response, idle quality and long-term engine cleanliness. OEMatch supplies replacements and related hoses prepared for Porsche applications to support routine maintenance and rebuilds.
Available Types- Oil separators (breather housings)
- Breather hoses and vent lines
- Seals, grommets and connection fittings
OE (Original Equipment) refers to parts matching original specifications for the oil separators & vent lines and may be supplied by alternative manufacturers. Aftermarket parts offer alternative options, sometimes with enhanced features or better value. OEMatch supplies non-OEM oil separators & vent lines engineered as direct-fit alternatives to OEM parts, made to original-spec dimensions and tolerances for Porsche models.
The oil separator and vent system controls crankcase pressure, removes oil vapour from circulating gases and keeps intake air free of oil droplets.
When functioning correctly the system prevents oil entering the intake tract, reduces smoke and limits carbon build-up on inlet valves and ports. OEMatch also maintains a catalogue of more than 4,000 individual part numbers and over 8,700 OE cross-references to aid correct selection for Porsche applications.
- Restores clean airflow and stable crankcase pressure
- Reduces oil leaks, blue smoke and carbon accumulation
- Supports consistent idle and throttle response
- Clogged or degraded internal membranes inside separators
- Cracked, hardened or collapsed breather hoses due to heat and age
- Worn seals, grommets or connection points causing leaks
- Vacuum leaks affecting idle and throttle response
- Sludge or condensation build-up inside vent lines
Replacing a worn or damaged separator or vent line restores correct crankcase breathing and helps avoid progressive engine issues such as oil contamination, valve deposits and inconsistent running. Fitted components specified for Porsche engines help preserve emissions performance and reduce the risk of oil reaching the intake tract. Select parts that match the original connections and materials for reliable long-term operation.
Advantages- Direct-fit replacements engineered to match original dimensions and tolerances
- Components manufactured in heat- and oil-resistant materials for longevity
- Catalogue cross-references and part numbers to support correct selection for Porsche models
Installation should be carried out by a qualified technician following model-specific procedures and torque settings. Use calibrated tools and new fasteners where specified. If you are unsure about hidden sensors or routing, seek professional installation to ensure correct sealing and operation.
.jpg){kind=link}
