SKU: 06L121081K
Audi Genuine Engine Coolant Breather Pipe - 06L121081K

This component is an integral part of the engine's closed-loop cooling system. Its primary role is to connect the coolant expansion tank (reservoir) line to the coolant hose flange connector mounted in the cylinder head just above the turbocharger assembly. It ensures efficient coolant flow, feeds excess coolant back to the overflow bottle, and prevents air pockets from forming within the engine block and turbocharger cooling circuits.

Because it is an original equipment manufacturer (OEM) part, it is constructed from durable, heat-resistant materials designed to withstand the high-temperature environment of a turbocharged engine bay.

Common Part Name Variations

Depending on the catalog or supplier you look at, this part may be listed as:

• Coolant Bypass Hose / By-pass Hose from Reservoir

• Engine Coolant Breather Pipe / Vent Hose

• Engine Coolant Overflow Hose / Vent Tube

• Radiator Coolant Hose

Vehicle Compatibility

This part is explicitly designed for Volkswagen Group vehicles equipped with the 2.0L L4 turbocharged (2.0T) gasoline engines. It provides direct fitment for the following models across various trims (Premium, Premium Plus, Prestige, and Allroad):

• Audi A4 / A4 Quattro Sedan & Wagon: 2017 – 2021

• Audi A5 / A5 Quattro Coupe & Sportback: 2017 – 2020

• Audi A6 / A6 Quattro Sedan: 2017 – 2018 (and select 2012-2016 model configurations depending on engine choice)

• Audi Q5 / SQ5 Sport Utility: 2018 – 2020

• Brand: Audi

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