There is a mysterious water leakage on the floor of the car on the drivers side and the rear drivers side floor. It's been in for a service and the garage can't work out where it's coming from.

The car is cat c damage repair and was bought in summer (no rain). Evene when it first started raining there was no leak in this part of the car. It was on the front passengers side and seemed to be caused by the fans when it was turned on full.

Theres no water around the sides of the interior, on the seats, or anywhere else. Just the base of the floors.

Where could it be coming from?

I bought this Focus for my daughter to drive and after a couple of weeks she complained of water collecting on the front passenger floor. After checking all possible causes I came to the conclusion that it was coming in through the fresh air intake. The intake had no filter in place. After going on the web I found out certain models came without any filter installed. I also found out that the problem is a common problem to that car. I installed a filter and tried to position some hard plastic over the intake to deflect any water from entering. It seemed to work for a while until the plastic moved and again we ended up with a puddle on the floor. I have still not come up with a permanent solution. Any ideas would be greatly appreciated.