The water pump on a 1998 Chevy Malibu is located at the
front of the engine, typically driven by the serpentine belt. To be more precise, it's on the
bottom of the engine, near the crankshaft pulley. You'll likely need to access it from the front of the vehicle, possibly removing some belts and accessories to reach it.
However, without knowing the exact engine size (there were several offered in the '98 Malibu), this is the most general location. A repair manual specific to your vehicle's engine will give you the most accurate visual information.
