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Frequently asked questions about cars and motorcycles

Instructions for Replacing Thermostat

Model: Audi A4 B6 - Years 2000-2004
Part: Engine coolant temperature sensor

The thermostat is located at the rear of the engine, in the center position, right in front of the battery compartment located just below the windshield. Start by opening the front hood, removing the intake duct, and disassembling the engine air filter housing by disconnecting the hoses and the mass air sensor connector. Remove the aluminum cover located on the side of the engine block; then the metal fittings that run along the side of the engine toward the thermostat: be ready to replace any rubber fittings that may be damaged during disassembly. At this point, remove the thermostat by first taking off the vacuum actuator connected to the engine block, which is right in front: there is little maneuvering space, and the operation is not that simple. Once the thermostat is removed, clean its seat on the engine block thoroughly and proceed with the installation of the new one, including the temperature sensor and gaskets.

Updated on 11 February 2026 by ScegliAuto

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