PontiacBonnevilleClub.com

So for the past probably 2 or 3 weeks my entire interior of my car has had tons of moisture in it. Every window is completely frosted/fogged over after i start it or after getting into it. Beads of water accumulate on my rear window, and even the bottom of my seats and carpet just feel kinda moist (front carpet only). My sunroof is completely iced over with frozen beads of water making visibility impossible through it. Ive brought it inside the garage for the last 3 weekends and dried all the water out and put a fan on it, and it helps for like the rest of the time its in the garage, but as soon as i take it somewhere again they all fog up. Any idea what this could be?

One possibility is a leaking heater core.
This will make the front carpet wet and fog up the windows.

These cars are also notorious for having sunroof drainage tube leaks, as well as other leaks, detailed in the Interior section here http://www.pontiacbonnevilleclub.com/fo ... 25362.html

Thanks! Ive already fixed the trunk leak, the door leaks, and all sunroof drain lines work good yet. Figured i should add that there is a weird smell in the car sometimes (like antifreeze, kinda sweet).

Thinking its the heater core? How hard would that be to change out?

I've had my entire dash out at least three times and have become quick and efficient doing it (which is necessary to replace the heater core). I'd consider this a big job for most people.

Just replaced my heater core last month.

You can check to see if it is leaking by removing the hush panel that hides the bottom of the blower motor under the glove box. It isn't a terrible job, just time consuming. I'd recommend removing the center console, as that extra 30 minutes of work will make your life so much easier in the long run... I only say this because I didn't... And it was a magic trick to get that old core out and new one in.

Just curious.
Is the GXP that much more difficult then the SLE?
Also did the dash have to come out on the SLE like it did on the GXP?

From what you are describing it would seem to be multiple water leaks, especially if the conditions improve when the car is parked in the garage. A leaking core would fog the windows regardless where the car is parked. To confirm it's the heater-core- does it smell like maple syrup in the car? Is your coolant level dropping?

Coolant level has dropped from where it normally sits in the reservoir, and yes there is a weird smell when the heat is on. and i apologize for the weird wording - it fogs in the garage too. so it fogs everywhere. mostly on passenger side.

Well that sounds like the symptoms of a leaking heater core! Good Luck with the replacement.

dougtoth wrote:Just curious.
Is the GXP that much more difficult then the SLE?
Also did the dash have to come out on the SLE like it did on the GXP?

So looking through the manual, it is possible to change the heater core without removing the entire dash. I thought when I had my dash out it was buried a little deeper. The process is a little easier for cars without automatic climate control. The space in the engine compartment is tighter for the GXP, but either way, that shouldn't be too much of a challenge with the right tool to remove the clamps for the heater hoses. It still is a bit of a pain. GM talks about one of the screws being so difficult to access that they say not to bother reinstalling it when you put it back together.

ddalder wrote:I've had my entire dash out at least three times and have become quick and efficient doing it (which is necessary to replace the heater core). I'd consider this a big job for most people.

Are there any instructional videos on how to replace the heater core? Mine also needs replacing.

mcdavidhome wrote:

ddalder wrote:I've had my entire dash out at least three times and have become quick and efficient doing it (which is necessary to replace the heater core). I'd consider this a big job for most people.

Are there any instructional videos on how to replace the heater core? Mine also needs replacing.

I did this years ago with limited wrenching ability. Remove the passenger seat and the center console and this will be a generally pretty obvious and easy job, just takes some time and patience.