i park my toyota avensis in the car park at work at the same time as everybody else.When it comes to leave work 9 hrs later my front window is fogged up and the glass is wet inside.none of the other cars are like this.iv only had it a month its a 2004 t sprit model.
there is obviously something wet inside the car,that is condensing when the car is left,
These problems can be a right pig to find,are there any wet mats in the car,? check windscreen seal, also sunroof for water ingress, is there a sweet smell inside the car that might indicate a leak in the heater, as antifreeze has a sweet smell when condensing,
I could fill a couple of A4 pages with possible causes.
If it's any consolation, I have a 1 yr old Mitsubishi Pick-up and it does the same. I have to use a squeegee thing inside the windscreen. I've wondered if it's where I had the aircon on when I've parked and left the vents open for the windscreen and the moisture has seeped in. Try parking with the vents closed. Just a thought.
Try lifting the mats up and pressing hard down on the carpets. You can get water ingress around the tailgate and sometimes the water tracks down to the lowest point. Also check the rear light seals and in the boot. good luck
I carry a kitchen roll in my car for this purpose with a small bottle of washing-up liquid. Just a couple of drops on the paper also helps to stop misting up until the fan dries the windscreen. I have trouble with the `header-tank` on mine leaking and it`s too dear to repair.... Ford Scorpio.
To dry out the car fully, always use your air conditioning(on a hot setting in this weather), as this will remove the moisture.
Make sure your air is not set to recirculate, as this will prevent the moisture escaping.
If you could leave the car running for a couple of hours with the heating on full, it will probably prevent the fogging up, unless you have a water ingress problem.
I work in a Toyota dealership and haven't been aware of specific leaking problems with this model of Avensis.