I bought a '01 Lesabre the other day for a replacement work car. Super clean low mile car from an elderly gentleman, I really enjoy driving. I have noticed one problem. Occasionally fog starts to build at the bottom of the windshield in one spot on the OUTSIDE of the windshield. After a few miles it will dissepate and go away. The defrosters won't take it off. When I bought the car it was low on coolant, reservoir was almost empty. I had a garage replace a radiator hose, thermostat and flush the cooling system, replacing the coolant. They said they couldn't find any coolant leaks. After having this done, I noticed it did it again tonight driving to work, then after a few miles it dissepated. Looking under the hood I can't see any evidence of a coolant leak. The car does have a cabin air filter located on the passenger side at the base of the windshield, I checked that just because I hadn't previously. It is very dirty and I will replace it tomorrow. Could that plugged cabin air filter have anything to do with this? I wouldn't think so, but anyone every have this problem or have an idea what's causing this? It is hot and humid here and I was using the A/C, but it only does it occasionally then after a while dissepates.
Sounds like some really cold air coming from the A/C system is going up through the defrost duct and chilling the glass locally. The fog you see is moisture from the outside air condensing on the glass. Then the A/C system (climate control) warms up the air a bit and the fog goes away. I would not worry about it. Jim
