Today: Tom and Ray help Annah de-leakify her Camry's roof.

Dear Car Talk | Nov 01, 2010
Dear Tom and Ray:
A few years ago, our 1998 Camry started to leak water inside. This is a problem in Oregon, so we took it in for repair, and 500 dollars later, they told us that they cleared the "weep channels" in the sunroof. Evidently, debris from parking under various trees gets into the weep channels and clogs it up, thus creating some kind of backflow that then pours and drips onto the floor of the car. Now, five years later, it's leaking again (even though we've been covering the car with a cover in leafy weather). I have this idea that we can clear the channels ourselves, but am unsure of exactly how to do it. We tried opening the hood, clearing out the debris and spraying water full-force into the holes near the outside edges of the hood. It helped for a few days, but then, of course, it rained again (and again and again - this is Oregon), and it began leaking again. Is there some other access to the weep channels? Can I get to it with an air compressor or a hose to clear it? In the meantime, I am air-drying the car, trying to keep mold from forming. Help! - Annah
TOM: Well, before you bone up on your drain-blowing-out skills, Annah, you want to be sure that it's actually the sunroof that's leaking.
RAY: Right. In our experience, leaks like this are much more likely to be coming from a bad windshield seal.
TOM: So start by taking a roll of duct tape (it comes in many exciting colors these days) and taping the seams of the sunroof shut. That'll keep any new water from getting in there. If, after a few days or a week, you continue to get water in the car, then you know it's not coming from the sunroof.
RAY: If, on the other hand, the car does dry out, then you either can leave the duct tape in place (which is what my brother would do), or you can try cleaning out the drains.
TOM: There are two drains on this car, and they run from the sunroof down each of the A pillars (the vertical pillars between the windshield and the front doors), and then empty out behind the front tires.
RAY: If you open the sunroof and slowly pour a cup of water in there (not into the open hole, but into the channel that surrounds the opening of the sunroof), you should be able to see if the water is draining out of there freely.
TOM: If it's not, check for debris in the pan where the water collects. Removing the debris may do the trick.
RAY: If there's no visible debris in that pan, the debris may be further downstream, in the rubber tubes that carry the water to the ground. I wouldn't blow compressed air in there, because you may blow the tube right off.
TOM: So if you haven't done that already, Annah, take a thin piece of wire, like mechanic's wire, and try working it down the tube and pushing out any debris that way. Then test it again with some water.
RAY: If the tube itself has become disconnected - on its own, or due to Hurricane Annah's compressed-air hose - then you may have to call in professional help. That requires pulling down the car's headliner. Which actually isn't very hard.
TOM: No. But getting it back up is. And if you don't want it to be sagging down onto your head and giving you bad-hair days forever after, it's best to let a professional handle that job. Good luck.