Jaguar Forums - Jaguar Enthusiasts Forum - Mildew and slight rust issues under floor mats.

Hi TattooB,

Moisture collecting in the floorpan is often an indicator of clogged sunroof drains, clogged A/C Evaporator drains or torn door weatherstrip allowing water into the passenger compartment.

There are drains at all four corners of the sunroof frame (not the sliding panel, but the supporting frame). You can carefully work something stiff but flexible such as string trimmer line down each drain to work seeds, leaves and other obstructions out, but take great care not to disconnect the rubber elbows that connect the hoses that run down the A- and C-pillars to the sunroof frame. In fact, a rubber elbow that has worked loose from a hose is one known source of leaks into the passenger compartment, so check your pillar trim, the bases of the A-pillars, and the corners of the rear seat for signs of water. These elbows are also the reason it's not a good idea to use compressed air to try to clean these drains.

There are also drains that run on either side of the transmission tunnel from the tray under the A/C evaporator in the center console down through the floorpan to allow condensation to flow out. But the drains tend to become clogged with deteriorating foam insulation, which allows water to pool under the evaporator and to slosh over the edge into one or both front footwells while cornering. In some models you can run string trimmer line from under the car up through the drain tubes all the way to the evaporator tray, but on other models obstructions at the top end require a drill bit to work through to clear the drains. The ultimate solution is to remove the dash (not as difficult as it sounds) and vacuum out all of the deteriorated foam insulation crumbs.

Also check your door weatherstrip for any possible leak points.

Cheers,

Don