ok.. it's a long process but it has never failed me. 1. GUT the area where water is. inspect the area to see if you can find a trail of where it's coming in......and then dry throughly... this will allow you to see a water trail if there is one (it's getting in somewhere so there has to be).
2. start low... water doesnt run uphill. soak one thing at a time then check it. soak another thing then check it. as soon as you start to see a trail form you know where to start looking outside for the problem (where you just soaked after your last check)
3. when you see where it's coming in and possibly where it's gettin in from outside.. use some type of foaming spray (foaming window cleaner works well).. spray it and let it foam where you think it's coming in. Then using a air compressor and airgun plow pressureized air though where it's coming from on the inside and see if any of the foam bubbles. if so that's where your leak is.
4. fix that leak...
5. check everything again. start low.. look inside for a drip or trail from a drip... and repeat steps 1-4.
depending on what is letting the water in there are several ways to fix it.
when i say gut the area.. really gut it. pull the carpet.. the plasic pieces by the door entry.. kick panels.. everything. it could be coming in under the dash somewhere.. the cawl.. or following the door rubbers from the top of the door or anywhere along the door and getting in.
good luck it's a time consuming process but a leak has never gotten away from me
