Originally Posted by wfhenderson

Hello all-- After finding water on my interior floors after a heavy rain more and more frequently, I suspected that my windshield seal was bad. Much testing with a hose would not duplicate the problem. Water was dripping out behind the glovebox. I searched threads here online and found that while the windshield seal can sometimes be the culprit, as can the wiring loom entry point at the firewall bulkhead, especially for those who have run additional wires there; this was not my problem.

If you are finding puddles of water and soaked carpet inside your Infiniti g35 or g37, it is quite likely that the culprit is your sunroof drain tubes. While the sunroof is meant to seal tightly when closed, it has rain gutters inside to catch water that inevitably gets past the seals. There are four drains, one in each corner or the sunroof opening. The front ones are hidden within the sunroof trolley rails, but if you stand on a stool and look closely At the black plastic caps on the front of each rail you will see the small openings. The rear openings are not visible , even with the roof panel open, as they are still covered by the sliding roof panel.

There are long plastic tubes connected to a nipple on each of the four corners, and these connections are usually the source of the leaks. They're narrow and clog easily with debris. The tubes run from the sunroof corners down each of the four roof pillars and exit underneath the car. If you open the sunroof and carefully pour a glass of water in each corner of the sunroof gutter inside , look underneath the car and you should see the water pouring freely out of access holes. If not flowing freely, that tube may be clogged or even partly disconnected from its rooftop nipple.

Fortunately, this fix is practically free and most people will be able to fix it themselves. Unfortunately, fixing this problem usually requires the partial removal of the headliner to access the leaks. You can try to use compressed air to blow out the offending tube without disassembly, but you may instead serve to dislodge the tube completely from its nipple and force disassembly anyway.

The instructions for dropping the headliner can be found in the interior section of the shop manual, available online at http://x.infinitihelp.com/forum/loca...3#.UrX0PmRDszI. You don't have to remove the headliner entirely, but you do need to remove enough fasteners at the corner of the roof on which you are working to pull it down without force. Avoid bending the headliner which will leave permanent marks and creases. Wash your hands well before starting to handle the headliner. It is next to impossible to clean if you get your greasy fingers all over it.

In my case, the front passenger side was leaking. The carpet was soaked after a heavy rain. Look for the HIGHEST place you have seen water dripping from. It is too easy to start taking things apart from the bottom, working up from the floor, and behind the glove box since that's where you see the water dripping out. Like many of you will find, my leak was originating at the very top where the hose connected to the rain gutter nipple. Infiniti simply installs the hose slipped over the end, with no clamps or sealer, which is not the way I'd do it if I was building this assembly.

Pulling the headliner down and away, I was able to install a small screw hose clamp on the connection, which fixed the problem instantly. Installing the clamp is easy The hardest part is lowering the headliner.

Finally, if you have had such a leak, this last step is very important. If your car smells musty inside or the windows steam up when the car sits closed up, be aware that the floor of the Infiniti has large, deep troughs beneath the carpet which are filled with blocks of styrofoam. These are there as part of the sound deadening and structural rigidity engineering of the car. But they can hold over a gallon of water each. It shocked me to see this when I removed the carpet. If you do not remove the carpets and empty and dry the troughs and rug padding, no amount of air freshener will ever make your car smell good again.

The photos below show the headliner pulled away and the tube attached without a clamp, the clamp added, and the floor with the carpet pulled back and the styrofoam blocks removed (and the hairdryer added!)

Hope this, helps!

new member Bill Henderson

Originally Posted by silverbird

Doug, did you resolve your issue? I had a similar issue with a recently purchased 2013 Infiniti G37X sedan. After trouble shooting and reading on the forums, my problem was the front passenger sunroof drain leaking into the cabin. The problem was at the grommet as you found. I spent hours, disassembling, cleaning, letting everything dry, reassembling etc. Problem solved. Or so I thought. A few days later I discovered the right, rear carpet wet. I thought I had a new/unfound leak. I used floor jacks to lift the front of the car and carefully poured water at the rear corners of the sunroof (with it open) to see if it drained freely. It did. I disassembled the trim pieces at the B-pillar to see if I could see any water flow. I did not. Further, at the bottom of the B-pillar, the sheet metal is angled outwards, away from the cabin so even if the water did flow down the pillar it appeared it would flow outside.

I removed the rear seat bottom, the passenger seat and associated trim to lift the carpet. I assumed the structure under the seat wouldn't allow water to flow to the back of the car--I was wrong. The water on the right rear floor of my car came from the original leak at the firewall. I allowed everything to dry and reassembled. The car has been through a car wash, a heavy rain and I poured water down the four corners of the sunroof to examine how readily the water drained--problem solved.

I hope this helps you or someone else.