Media & TV0 min ago
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You do not mention the make of car, but some cars are very prone to letting water in. One cause might be door seals, however there are other sources of leaks also - for example some models of VW Golf (the Mark 2 in particular) have a feature which is extremely leak prone. As a first step follow advice already given and lift the carpets (especially both sides in the front) including the padding under them. If at all damp (possibly getting smelly too), remove and dry out thoroughly. While the carpets are out observe whether water is showing on the floor - allowing for wet feet carying it in. If water is coming in try to find the location of entry. This can be a very frustrating exercise (consulting knowledgeable people about your particular model may help) because water can trail unseen before it energes. In the Golf (above) the thin plastic tray under the bonnet and below the winscreen (black and shaped to drain water into the run-off drain) frequently cracks because it is so brittle. Remove carefully and check for cracks, including by holding up to light. It is possible to repair by cleaning and drying thoroughly followed by putting generous beads of silicon where they do not interfere with the way this piece fits into the car. Refit very carefully or you'll crack it again somewhere else. You could buy one new at enormous cost from VW, but better still go to a scrap yard. Best of luck.