Breather Line. Porsche 996 Carrera / Turbo 1998-05  ❭  99610676

Breather Line.
Renew the ventilation path on your Porsche 911 (996-series) with these genuine breather / vent hoses. Designed for 1998-2005 911 (996) models (including Carrera, Turbo variants) these hoses ensure your engine’s breather or cooling-vent line operates correctly—preventing vapour or pressure buildup, supporting correct engine ventilation and maintaining system reliability.

Fits:

• 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

Diagram Ref No 21 And 22

What This Product Does:

• In the context of the engine / cooling / ventilation system, a “breather line” or “vent hose / vent line” allows controlled venting of crankcase or cooling system gases, or supports the cooling/overflow/expansion system to relieve pressure, direct vapour, or provide required venting.
• These hoses ensure air or vapour that builds up is not trapped in the engine/cooling system, allow system pressure to stabilise, and maintain correct service behaviour of the engine’s ventilation or cooling circuits.
• They also help prevent buildup of pressure/vapour that could otherwise lead to malfunction, leaks or driveability issues.

Symptoms Of Wear, Damage Or When To Replace:

• Hose visible damage, cracking, brittleness or detachment — Over time, heat and age degrade rubber/hose materials.
  
• Engine or cooling system venting issues — for example, if you smell vapour/odour, see coolant or oil vapour escaping in unusual places, or lid caps popping off unexpectedly.
  
• Unusual noise or hissing from the engine bay or venting hose areas—possibly indicating a leak or damaged hose.
  
• Performance degradation in the ventilation/cooling system—such as elevated temperatures, pressure spikes in cooling, or increased oil consumption if the hose is a crankcase breather.
  
• Poor condition hoses in older vehicles—since these parts are often overlooked in maintenance, especially with older 996 models, they may be degraded and benefit from preventive replacement.
  
  

Why Replacement Matters:

• Maintains correct system function: A properly functioning breather line ensures your engine’s ventilation/cooling systems are working as intended — preventing pressure buildup, vapour trapping or system inefficiencies.
• Prevents secondary damage: A failing hose might lead to undue pressure or vapour escaping in unwanted places, which can damage hoses, connectors, engine seals or other vulnerable parts.
• Helps reliability and longevity: Especially in older 996 models, replacing old, brittle, cracked hoses with fresh OEM-spec units avoids failures that can strand the vehicle or lead to more expensive repair.
• Peace of mind & maintenance value: Ensuring the ventilation path is intact supports the overall health of the engine and cooling system, which can matter for resale or restoration quality.

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

99610676

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