Engine Water Pump – ACDelco (252-1003)

Engine Water Pump moves fluid or air through the circuit at the volume the calibration expects. Output falls off gradually, so the complaint usually appears as a loss of performance under load rather than a sudden stop.

Replace the Engine Water Pump when output has dropped enough to set a performance code, when the drive belt slips only on that pulley, or when the housing weeps at the seal. Rule out a restriction first, because a blocked filter mimics a failing pump.

Ordering reference for the Engine Water Pump is part number 252-1003, categorised under Water Pumps. Match that number against the component you are removing before you order.

This is ACDELCO dealer-sourced stock rather than an equivalent, so the number on the Engine Water Pump traces straight back to the manufacturer.