the Fatwa Department Research Committee - chaired by Sheikh `Abd al-Wahhâb al-Turayrî
The correct position on this matter and the one held by the majority of scholars is that intention is a requirement of wudû’, since performing wudû’ is a pure act of worship.
Performing wudû’ is not like washing a stain of impurity off of clothing. Washing something off is an activity that clearly does not require a specific intention, since the removal of physical impurities can occur without one. Wudû’, by contrast, is an abstract and formal act of worship that cannot be grasped by our intellect.
To illustrate this point, we should consider that when we pass gas, we must perform wudû’ before we can pray. When we do so, we must wash our faces and our feet, but we do not have to wash the affected area.
Therefore, there is no wudû’ without a specific intention for wudû’.
The Prophet (peace be upon him) said: “Actions are but by intentions and every man will get only what he intended.” [Sahîh al-Bukhârî and Sahîh Muslim]
Source: Islam Today