2007 G35- after heavy rain I have water on my passenger side floorboard. It looks like it is possibly running in from along the door pillar. I removed the trim along the bottom of the door and pulled up the carpet and found standing water. There is a small cavity under the white foam insulation under the carper which is filled with water. My guess is there is a drain blocked somewhere buy don't know where. Where should I look?

 

Look for lots of other threads here about water leaking at the windshield/dash area. The usual suspects are the windshield sealant (particularly in the case where a windshield has been replaced), the grommets along the firewall under the hood (particularly the one behind the battery and extra particularly if you've had any aftermarket wiring work done on your car), a clogged/broken condensate drain on the AC/Heater unit, and lastly, a clogged/broken moonroof rail drain (I thought they came down the A-pillar, but I could be mistaken on that).
Good Luck.

 

My guess is the moonroof drain, happens to my mother's car all the time.

 

This was my problem.

 

I have standing water on my passenger floor board also. I have gotten the moonroof drain cleared my the dealership atleast 3 times and this problem is still an issue. You think it can me the windshield?

 

How can I access the moonroof drain?

 

I have or had the same issue but since I am in AZ it rains minimally but last heavy rain it did it. I recently had my windshield replaced and they came to my place and took off the trim and said it was sealed properly but still think that is my problem but with minimal rain its hard to tell. I would consider the windshield as well if replaced recently.

 

Its most likely your roof, fixed mine about 2 weeks ago but mine was leaking on drive side. Really easy to fix if you open your roof all the way back, you will see two holes, one in each corner thats were the water drains get some weed waker line and run it trough just to clean put the tubing the tubing runs along side the windshield pillars they pop right off and you can see if anything is clogging it in there good luck

 

You are lucky it didnt trash the BCM. thats right threre in the passenger side kick panel.