Timing Belt Kit Water Pump Gasket Fit 01-06 Audi A4 Quattro VW Passat Turbo 1.8. Located in the engine compartment behind the drive belts, the timing belt keeps the crankshaft in sync with the camshaft(s), essentially ensuring the proper timing and operation of the engine and its valves. When replacing a timing belt, also replace tensioner, and pulleys. Failure of pulleys and tensioners, after replacing only the belt, can cause valve or piston damage and lead to more expensive repairs. Additionally, timing belt driven water pumps should also be replaced at the same time as the timing belt. Operated by the drive belt, the water pump's core function is to allow coolant to flow into the engine continually. Together, these three components: timing belt, tensioners and pulleys, and the water pump are essential to the overall health of your engine. Ignoring the replacement of a timing belt as a part of scheduled maintenance could result in major engine failure down the road. Be sure to use our aftermarket replacement timing belt kit when the timing belt is serviced for the best performance.