i have a 96 deville and when i drive the windows seem to fog up wen i just start off, n they fog up so bad that i have to turn on the defog for a min or two to get them un fogged and then they just do it again, it only happens sometimes, but wen it does its non stop all day, could this be a sign of a bad heater core?

Two things, do you have a smell of antifreeze in the cabin, that is a sure way of knowing if you have a leaky heater core.

Second, are you driving with the Recirc button pressed in? That would also cause your windows to stay steamed up. Lastly when you hit the defog, it automatically stops the recirc and brings in fresh air.

Check your DIC for codes, on your car it will be under the ACM, maybe the programmer is pooched and is shutting your airmix doors at the wrong time. Just a thought.


Good Luck and let us know what you find..

From your discription I would almost guarantee it is bad heater core. I would bet the condensation on the windows is somewhat oily, right?

yeah it smells like anti freeze wen i idle for long periods of time and sumtimes wen i first put the heat on, and yes it is oily

It's heater core time.

well thats not bad, but the heater core is behind that big ole dash isnt it?

Yeah, I think it is on the passenger side and may be accessed from the bottom but I am not sure as I have never had the "pleasure" of doing one. I'm sure some one who has will chime in.

aight thanx, n yes if any has please chime in and tell me how it was..please