Genuine 4E0121109M Engine Coolant Reservoir Hose - Lower

Engine Coolant Reservoir Hose for Audi V8 Cooling Service

This Genuine engine coolant reservoir hose is a direct-fit cooling system component for select Audi V8 applications. It is built for the lower reservoir connection and supports proper coolant routing in the engine cooling circuit.

Key Features

• Genuine OE replacement part
• Part number: 4E0121109M
• Lower engine coolant reservoir hose application
• Fits 2005-2009 Audi A8 Quattro, lower
• Fits 2007-2009 Audi S8, lower

Detailed Description

Genuine 4E0121109M is an engine coolant reservoir hose made for lower-position cooling system service on the Audi A8 Quattro and Audi S8. Use this part when replacing a damaged, leaking, or deteriorated coolant hose in the reservoir circuit. The OE-style fit helps maintain the original routing and connection points used on 2005-2009 Audi A8 Quattro and 2007-2009 Audi S8 models. Part number 4E0121109M is the reference to verify application before ordering.

Common Repair Reasons

• Coolant seepage at the reservoir hose connection
• Cracked or brittle hose material from age and heat
• Loss of coolant from a damaged lower hose
• Incorrect hose routing after prior cooling system repair

Installation Notes

Confirm the lower hose routing and connection style against the original part before installation. Drain coolant as needed, inspect adjoining fittings and clamps for wear, and refill the cooling system according to factory service procedures after replacement. Verify there are no leaks and that coolant level remains stable after the engine reaches operating temperature.

Quality Assurance

Genuine parts are produced to OE specifications for the listed applications. Verify fitment by matching the vehicle details and part number 4E0121109M before installation.