How to Check Water Pump Impeller 2 liter engine (AEG)

Abstract: This article provides an overview of repair and diagnostic information related to the following procedure: Water pump impellar.

Applies to: VW Jetta, Golf, GTI 1999 - 2006, R32 2004 - Engine Code AEG (Volkswagen A4 platform)

2.0 Liter engines come equipped from the factory with a plastic impeller on the water pump. The impeller fails over time and cause a loss of engine cooling (engne will overheat) and a loss of cabin heating (no heat in interior of vehicle). Using the following procedure the impeller can be quickly diagnosed.

The following photo shows a failed plastic water pump impeller.

• Remove thermostat.

• Insert gloved finger into thermostat mounting hole (inset). try to turn impeller with gloved finger. If impeller moves freely it has failed.