2004 Lexus RX330 AWD is the victim.

Yes, I've read the sunroof drain threads, all of them from various forums. All was well, as I tackled this 2-3 yrs ago. So much, as enlarging the holes in the "box drains" within the rocker assy., making holes in the floor board grommets to prevent any pooling water.

Once I cleaned it out, I was fed up. At the time my dad was still driving it and never used the sunroof - so... I disconnected it & ran a bead of silicone (or was it urethane?) ALL around the sunroof, gasket & paint work to make a permanent seal.

All was well for ~2yrs.

Fast forward now, my brother drives this thing... and the floor is wet. The rear passenger floors are soaked. The fronts are damp-ish.

I didn't have a chance today to rip apart the trunk area, but through some of the screws in those stupid, stupid pocket/storage bins, I noticed some water. I have to pull out a subwoofer as well to get to it, so its... a project to do... Before anyone says it - the seam sealer at the roof line is fine, not exposed like some of the ones' I've seen. The gaskets on the tails were "okay" when I had them last out ~3yrs ago (I replaced the trunk lights due to chrome peel/delamination)

Anywhere I can miss? The car does get undercoated and I know the little veins that run down the rocker, where the water should be draining have a low chance of build up. But not sure what else I can do with this ****ng thing... I'm stumped. I'm pissed. I'm frustrated, that Lexus has such a faulty design. I'm not talking too much **** here, as the car is very old now (still low miles) and it looks & drives A1., but it'd be nice to get a few more years out of the beater for my brother until he wants to buy something nicer for his own dime.

 

Hello,

Besides what you mentioned, you can dry out the interior as best as possible, maybe take most of easy to access plastics out, and go around the car with a pressure washer, use your own if you have one or visit a self-service car wash if you don't. Go heavy on the potential spots, like taillights, rear door and glass, sunroof, vent panels under the rear bumper, not sure if there is one on the left or on both sides. While interior panels are out, inspect for any potential rust spots around the rear quarter panels and under the bumper, dark garage and bright spot light should help, I am not sure what condition your car is in, but considering the area you live in, it might be worth a look.

P.S. About the sunroof, I believe they sell swap panels for a sunroof delete, it is much lighter and will never give you leak issues, as long as you do it right and don't need a sunroof in the first place. I like the sunroof, so I personally am willing to put up with it..

Hope this helps and best of luck!

 

This crap drove me up the wall with my 2002 Highlander. I had to replace the tail light seals, third brake light gasket (probably not likely to fail on an RX) and trunk seal before it stopped. There are some drains behind those rear cubby holders which can clog up and hold water. Have someone on the outside spray high pressure water at the rear of the car while you sit in the trunk and see if you can notice water coming in, that was what saved me so much trouble.

 

For sure, that's a typical plan of action... The one that stumps me is the REAR seat floor.
When the drain were clogging the first go, before I disabled the sunroof, it was only in the front. The rear was fine.

This was overall a surprising turn of events, it's been super rainy in our Ontario region for ~2days or so.

I'm thinking to rip apart the door sills, blast the drain cavity with water to loosen up any dirt and I'll just remove and reseal all around the tails & the top of the roofline where it meets the quarterpanel and hope it does the trick. As well as drill drain holes in any floor grommets.

 

I hope that does it! I have never heard of water getting to the rear floor, that sucks!