Heater hose - Engine to return line. Porsche 996 / 997  ❭  99610622275

Heater hose - Engine to return line.
OE Match heater coolant return hose is a direct-fit replacement designed to replicate the original Porsche hose used in the heater return circuit on Porsche 911 996 and 997 models. It carries coolant from the heater core back into the engine cooling system, supporting both cabin heating and overall thermal regulation.

Fits:
Porsche 996 Carrera 2002 - 2005 Tiptronic Gearbox only
Porsche 997.1 3.6L / 3.8L 2004 - 2008
Porsche 997.1 Turbo / GT2 2007 - 2009
Porsche 997.2 Turbo / GT2 RS 2010 - 2013
Porsche 997 GT3 3.8 / 4.0 2009 - 2011

Diagram ref no 42

The hose installs directly using original mounting points and standard Porsche hose clamps, making it suitable for both routine maintenance and larger cooling system overhauls.

The heater coolant return hose channels warmed coolant from the heater core back to the engine’s cooling circuit, completing the heater loop. This allows the cooling system to maintain balanced flow and ensures consistent interior heating performance.

Installed between the heater core outlet and the engine return line, this hose:
•  Maintains correct coolant flow and pressure in the heater circuit
•  Supports reliable cabin heating
•  Resists collapse, swelling, and heat degradation
•  Integrates with factory hose routing and connections
 Its OE-matched geometry ensures proper clearance and reduces stress on joints and adjacent hoses.

Over time, heater hoses deteriorate due to heat cycling and coolant exposure. A failing return hose can cause coolant leaks, reduced heating efficiency, air ingress into the cooling system, or engine overheating. Replacing worn hoses with an OE Match component restores proper coolant circulation and helps prevent unexpected cooling system failures.

When to replace:
•  Visible cracks, swelling, or soft spots
•  Coolant leaks around the hose ends
•  Heater blowing cold air, indicating poor coolant flow
•  Cooling system overhaul or heater core service
•  Preventive maintenance on high-mile vehicles

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99610622275

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