54 Reg Corsa glovebox removal

is it rainwater? I would be looking at the drains for the heater intake area being blocked, which is under the bonnet. when blocked the water sits there and sloshes about till it flows over and into the heater.

Hi Had the same problem with my Vectra, its the drain hole blocked. On the vectra under the bonnet, near the edge of the windscreen the plastic is cut so you can lift it up, put your hand down, aboyt level with the wiper bolts, and you will feel the rubbbish collected. It is a piece of squashed rubber that holds the dirt in the vectra, so if its the same just push your finger through and it will allow the water to escape. Its a common problem with vauxhalls apparently. Regards Pete