A failure in the water pump can cause serious engine damage due to overheating. Water pumps are equipped with weep or vent holes. If a failure occurs in the pump seal, coolant will leak from this hole. The water pumps on V6 models and 2006 and earlier four-cylinder models are located behind the timing belt covers. If you suspect water pump leakage, remove this cover. In most cases, it will be necessary to use a flashlight to find the hole in the water pump by looking through the space behind the pulley, just below the water pump shaft. A slight gray discoloration around the weep hole is normal, while dark brown stains indicate a problem. If the water pump shaft bearings fail, there may be a howling sound at the front of the engine while it is running. Bearing wear can be felt if the water pump pulley can be rocked up and down. Do not mistake drivebelt slippage, which causes a squealing sound, for water pump failure. This can occur on engines with adjustable drivebelts. Spray automotive drivebelt dressing on the belts to eliminate the belt as a possible cause of the noise.