Why does the Audi C6 make a squeaking noise when starting cold?

[DeFinn]

Audi C6 making a squeaking noise when starting cold is caused by the aging of the water pump belt or engine belt slipping, resulting in abnormal noise. Automotive Water Pump: Automotive engines widely use centrifugal water pumps. Their basic structure consists of components such as the water pump housing, connecting plate or pulley, water pump shaft and bearings or integrated bearing, water pump impeller, and water seal device, which are major components of a vehicle. Automotive Belt: It is an important part of the engine's valve train system, ensuring accurate intake and exhaust timing by connecting with the crankshaft and matching a certain transmission ratio. The use of belts instead of gears for transmission is because belts produce less noise, have minimal self-variation, and are easy to compensate. Obviously, the lifespan of a belt is certainly shorter than that of metal gears, so belts need to be replaced regularly.