This is sprocket pulley move on the front side of the engine and plays an important role for making the engine work, for driving several components, including the alternator, power steering pump, water pump, vacuum pump, and air conditioning compressor. Several arrangements are possible: a single belt, multiple belts; it is advised to check the belts for wear, despite the fact that they may last more than 100,000 miles. The lead is automatically set to the tension as required by the alternator and power steering and water pump belts, whereas the air conditioning compressor and vacuum pump utilize a "stretchy" belt with no tensioner. Before inspecting the belts, the engine should be turned off, the whole length of the drive belt(s) should be visible and examined for cracks, fraying or glazing of the surface, and the pulleys as well. Minor crack on ribbed belts are permissible as far as they are not serious or they penetrate through the belt's depth. For replacement the air intake duct has to be taken out and the position of the drivebelt has to be noted down before using a breaker bar to loosen the belt and then take it out. The new drivebelt has to be place on the right pulleys and needs to be set down before the air filter duct is put back into its position. The air conditioning compressor drivebelt requires the removal of the accessory drivebelt first, after which the old belt has to be cut or there is specialized tool that has to be deployed. The new belt is then driven on to the crankshaft pulley and slipped over the compressor pulley with a bar that has been inserted between them. The vacuum pump drivebelt is removed in a similar manner as is the new belt positioned correctly on the crankshaft and vacuum pump pulleys. For drivebelt tensioners the drivebelt has to be removed, tensioner removed from the engine and it has to be refitted together with bolts tightened to the prescribed torque.