Water on passenger floorboard maybe from window gasket?

Shannon L Washam

• 169 Answers
• Posted on Sep 24, 2009

SOURCE: water on floorboard on passenger side

It could be that the condensation drain line is blocked and backing up into the car - but; it is more likely that your problem is a result of a poorly designed cowl cover over the blower fan for your air conditioner. this is a VERY common problem on 97-03 Grand Prix's as well as Malibu's and Impalas through '04. The other side effect of this is that water draining into the blower fan WILL cause it to fail eventually - this solution eliminates that risk.

Here is the cowl (pictures from an '04 Impala, FYI, but are identical):

You will need to remove it by pulling the retaining clips up - there is 1 on each end, and then one towards the top that has a slot in it. Be careful to not break these or lose them.

Remove the cowl, and underneath you will see the blower fan:


Under the cowl you will see a rubber seal that is indicated by the arrow - this is the poorly designed "drip edge". You can either remove it - or leave it in place; the new diverter will accumulate any moisture captured by this seal and divert it properly.

Here is a picture of the part you need - which can be purchased from any GM dealership for about $4 - the GM part is #15794785. Most dealerships don't stock it - but they can order it for you.


It simply sits in place as noted by the arrows - you'll notice there is a long extension from the left side of the part - this is the "finger gauge" - you want this to be positioned as far towards the left (as your facing the motor, or passenger side) of the vehicle as possible.

Here is a close-up of the gauge to give you perspective on how it should be positioned:


This is a shot of the drain area that the new diverter will use - instead of dumping water into the blower fan like the old design.


Now - for the cowl to fit over the new diverter - you will need to trim a couple of pieces of plastic from the bottom of the cowl - as indicated:


You can simply use a utility knife and a pair of pliers to score and snap these pieces off.



What the underside of your cowl should look like after removing (lines indicate where plastic was removed)


No you can simply replace the cowl, and reinstall the retaining clips - and you are all done.

Hope this helps - be sure to rate it and comment! ;)

KC GTO Dad

Bill

• 424 Answers
• Posted on Oct 08, 2009

SOURCE: why does water get into the passenger side

There is a leak from your cowl area.There is a technical service bulletin to install a plastic extension onto the cowl cover so water will not leak in side. It will also damage your blower motor if you don't get it reapred.

SOURCE: Water leaks in the back passenger side of 2007 Equinox.

The spare tire well is pooling water, check there. GM knows about it, but won't say it's a factory defect. Sorry, I'm in the same boat you are. See here: http://ww2.justanswer.com/uploads/Bluegorilla/2008-10-09_134337_08-08-057-001a.pdf

SOURCE: WHEN IT RAINS MY PASSENGER SIDE FLOORBOARD FILLS

you have a leak going through a welded area. The factory uses a seam sealer upon building these cars. So to fix this when the entire car is assembled it quite difficult to do. First you have to locate the nature of your leak. If you can see where it is coming from, great. If not you will need to remove many articles from your car such as the carpet and backing which will have to be removed for proper cleaning from stagnat water sitting in place for sometime now. Any sound board padding going up behind your dash up through the firewall. When all that is removed you can see alot of sheet metal. Inspect all welded seams for traces of rust. That will be an earmark for a leak. Shine a flashlight as far as you can see looking for rust scales throughout.If you have to mix Arm & Hammer baking soda with water 50/50 mix and pour throughout the outside screen into the firewall and watch for that milky film seep into the interior. The soda will ellimanate odors as well for your car. I know this is a tough job which no mechcanic likes to tackle but it does happen to all of us at one point in our lives
Hope you find the leak and get it resealed with a 3M resealing product too
Good luck

SOURCE: the passenger side floorboard gets wet =

is it only when the ac is on? there is a pan under the ac unit that has a hole in it to allow the condensation to empty. if that hole gets plugged it could cause the condensation to build up and back into the inside of that car. i unplugged mine and floor stayed dry