sit in the car and have someone gently rock the car.
![](./images/smilies/spacer.gif)
You may hear water.
![](./images/smilies/spacer.gif)
Also, go into the cubby holes behind the seats and remove the side panels.
![](./images/smilies/spacer.gif)
Feel around behind here for water.
![](./images/smilies/spacer.gif)
If the drain holes block up the water is held in here.
![](./images/smilies/spacer.gif)
It may be just as easy to remove the plastic side vents and check the drain holes are blocked anyway(should be a routine item) There is a full guide somewhere.
![](./images/smilies/spacer.gif)
I would have thought that if there is a damp problem enough to cause mould you would smell it.
![](./images/smilies/spacer.gif)
See if you can find a way to remove the mould and then use a sanitiser spray
![](./images/smilies/spacer.gif)
(motorcycle accessory shops sell this)