It all started on a rainy morning. I brought my parents car up on the driveway to replace nearside/offside front drop links. Everything bolted up nicely and I went for a test drive. The new drop links worked fine but then there was something else.

As I reversed, or drove around corners there was a swishing noise coming from behind the dashboard, similar to what you would hear when water runs down the gutter. I've googled this and some have said it may be trapped water. Had a look around but I can't see anything. There are no leaks or anything of that nature.

If the water noise was coming in from behind the dash, where the hell would I start looking?

The car if it helps is a 1999 Mk1 Ford Focus 1.4, although I don't think that would really matter.