Coolant Leak from the Expansion Tank Hose?

Replace One of the Most Common Audi 2.0T Cooling System Failure Points.

The factory coolant expansion tank vent hose is responsible for routing coolant between the radiator and coolant reservoir while maintaining proper cooling system pressure and coolant circulation.

Over time, exposure to:

• constant engine heat
• pressure cycles
• coolant chemicals
• aging plastic connectors

can cause the original hose assembly to:

• become brittle
• crack suddenly
• leak coolant
• break at the quick-connect fittings

A failing coolant hose may cause:

✔ Coolant leaks
✔ Coolant spraying in engine bay
✔ Low coolant warning light
✔ Engine overheating
✔ Sweet coolant smell
✔ Steam from engine compartment
✔ Sudden coolant loss while driving

This OEM-style coolant reservoir vent hose is designed to restore proper coolant flow and cooling system reliability.

Manufactured from durable heat-resistant automotive-grade materials, it provides reliable direct-fit installation for selected Audi 2.0T TFSI vehicles.

Key Features & Benefits

✔ OEM-style aftermarket replacement
✔ Restores proper coolant circulation
✔ Helps prevent coolant leaks and overheating
✔ Durable heat-resistant hose construction
✔ Reinforced quick-connect fittings
✔ Designed for high-temperature turbocharged engines
✔ Direct-fit installation
✔ No modification required

Product Specifications

Part Type:
Coolant Expansion Tank Vent Hose / Coolant Reservoir Overflow Hose

Material:
Heat-Resistant EPDM Rubber & Reinforced Automotive Plastic

Reference OE Part Numbers:

• 8K0121081BF

Compatible With Selected Models

Audi

• A4 B8 2.0T TFSI
• A5 2.0T TFSI
• A4 allroad
• A5 Quattro

Compatible with selected Audi 1.8T / 2.0T TFSI applications.

Please verify OE part number before purchase.

Audi OEM parts catalogs identify 8K0121081BF as the engine coolant overflow / vent hose used on multiple A4 and A5 applications.

FCP Euro confirms this hose connects the radiator to the coolant expansion tank.