Audi S6/S7 Coolant Reservoir Breather Hose / Line Front, Left 4G0121081CQ

OEM Part #: 4G0-121-081-CQ (4G0121081CQ)

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The OEM Coolant Reservoir Breather Hose / Line (Part Number: 4G0121081CQ) is essential for maintaining optimal engine performance in Audi S6 and S7 models from 2014 to 2018. This component is located at the front, left of the engine bay, connecting the coolant reservoir to the engine's cooling system. Its primary function is to regulate pressure and allow coolant vapor to escape, ensuring the system operates efficiently. Common issues include wear, cracks, or blockages, which can lead to coolant leaks or overheating. If you notice fluid accumulation or engine temperature warning signs, it may be time to replace this part. Alternative terms for this component include vent tube and vent pipe. This genuine OEM part guarantees a perfect fit and reliable performance in your vehicle.

Specifications

Specifications for Coolant Reservoir Breather Hose / Line 4G0121081CQ
Fits Vehicle ModelS6, S7
Fits Vehicle MakeAudi
OEM Part No4G0-121-081-CQ (4G0121081CQ)
SideFront, Left
CategoryRadiator / Coolant

Compatible Vehicles

Fits 9 vehicle configurations across 1 make, 2014-2018.

Check your specific vehicle before ordering. This list shows year, make, and model. Some years have multiple trims or engines that use different parts, and individual listings may have additional fitment notes (e.g. “with sunroof only”). Review the full variant list below, or message us with your VIN and we’ll confirm the match.

Audi

  • S6 2014-2018 · 5 variants 2 with notes
  • S7 2014-2018 · 4 variants 1 with note
View all 9 vehicle configurations — 3 with fitment notes
Full vehicle fitment list for Coolant Reservoir Breather Hose / Line 4G0121081CQ
Year Make Model Trim Engine Note
2014 Audi S6 Sedan 4.0L V8 Turbo For Vehicles with Production Date After 05/26/14
2014 Audi S7 Hatchback 4.0L V8 Turbo For Vehicles with Production Date After 05/26/14
2015 Audi S6 Sedan 4.0L V8 Turbo For Vehicles with Production Date After 05/26/14
2016 Audi S6 Sedan 4.0L V8 Turbo
2016 Audi S7 Hatchback 4.0L V8 Turbo
2017 Audi S6 Sedan 4.0L V8 Turbo
2017 Audi S7 Hatchback 4.0L V8 Turbo
2018 Audi S6 Sedan 4.0L V8 Turbo
2018 Audi S7 Hatchback 4.0L V8 Turbo

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