It was about 65 degrees last night when I parked the Kitty after about a 30 minute drive in town and she was purring nicely, keeping her cool and elegant poise. I returned to her after about 45 minutes, started her up and the windows fogged up like I haven't seen since I was a young man.

I'm assuming the air inside the vents was still heated and as the system injected this hot air into the cabin, condensation occurred while coming in contact with the cooled windows.

I have never experienced this with a car and assume it's just a V-12/XJS thing. Anyone else experience this?

BTW, has anyone modified the ventilation system to draw fresh air inside the cabin (like on any base model Nissan or Honda, etc) w/o having to 1) open the windows or 2) activate the A/C compressor-Temp control unit?

Thank you for your comments!

 

I'm betting that your heater core is leaking (any sweet smell?) or your carpet pads are wet from a rain water leak or your heater/AC case has a pool of water in the bottom due to plugged drains. Have you cleared the drains lately?

Along those lines the beauty of having the compressor run all the times is that the air is always dehumidified...for comfort and fog free windows. Of course, it can only do so much so if there's a large source of moisture in the cabin....well...you know.

Here's a fresh air mod, though....

http://www.jag-lovers.org/xjlovers/xjfaq/freshair.htm

Cheers
DD

 

Oooops. Never mind the fresh air modification link. It applies to the older Delanair MkII system. You car has the MkIII system.

Cheers
DD

 

Thanx, Doug, but there's no sweet smell & carpet pads are dry as a bone....I did use water at low pressure to finish clearing rat debris and urine from the engine in May and have never cleared the drains.

Pardon my ignorance, but I'm not familiar with this procedure. Can you please elaborate?

 

With the car safely elevated (or on a hoist) look on either side of the transmission "hump" just aft of where the transmission and engine come together. You should see a plastic tube poking thru the floorboards on either side of the transmission hump. These are the evaporator drains. Use stiff wire (a coathanger will work but something slightly thinner is better) to gently probe into the tubes and clear any blockage. Bending the end of the wire into a small hook (1/8") will help pull out any debris.

Do not stand directly underneath the tubes or you'll likely get a face full of very smelly water ! I've see 'em where as much as a quart of water was trapped in the case.

You might have to repeat this a 2 or 3 times in the next few weeks as loose debris in the bottom of the case tends to re-clog the tubes.

You can do this job from inside the cabin by removing the console "cheek" panels to gain access to the drain tubes right where they attach to the evaporator case. They're a little buried in there but it's doable. You'll need towels under the drains (or a way way of diverting the water) so your floor doesn't get soaked.

Heh heh...sometimes the evap case get so loaded with water that it sloshes onto you feet while going around a corner. That's a real treat :-)

Cheers
DD