1. Bulkhead drain hole (under the bonnet) blocked by leaves? If so clear them out and run water through the drain hole to flush it - use a watering can.
2. Check your coolant level - your heater matrix might be leaking - the water in the car will have a sweet smell if it is this.
3. Windscreen leak. Check by putting newspaper down near the screen. If it gets soggy you'll know.
4. Door seal faulty, torn or not sealing.
ChicksFan, November 2012
