Defogging not sufficient

[Cara]

My '03 doesn't defog nearly enough. I'm constantly having to wipe down side windows with my sleeve to be able to see. I've followed much of the advice here about using the 2 different defog/defrost settings, and the A/C, and the recirc setting -- but, even with just me in the car, I fog up quickly when the outside temp is 35 or lower, whether my temp setting is warm or cool. Gets significantly worse when the husband and 2 big dogs are in the car with me.

Any suggested troubleshooting for this? How do I know if something else is going on?

Thanks

[vibrologist]

3 things to check:
1. cabin air filter.
2. the cable that operates the venting options. There is a TSB out because in some cases that cable was not correctly adjusted at the factory.
3. A/C drain. Make sure the condensed water can run off through the drainage hose. Check the passenger side carpet for moisture. If it is wet the hose may have come off and all the water collects in the foot well.

Also try keeping a rear window cracked open for direct venting.

[sideshowalan]

According to this:
http://sploid.gizmodo.com/heres-the-fas ... 1751085019

Recirculation off is best.
Do you have it on recirculate or fresh air?

[Cara]

Vibrologist - thanks. I'll look into all those (I think the cabin filter has been deemed clean, by my mechanic).

SideShowAlan - unfortunately, because my Vibe also suffers from the broken recirc gear (others have posted about it) - I pretty much HAVE to be OFF fresh air and ON recirc, all the time... In this case, that's a good thing, I guess!

[mr.clutch]

CARA , That is your main problem you need to fix the REC. MOTOR for your defrost setting to work ( windshield ). If you still have a problem after the repair you should make sure your heater core is not cracked or leaking. GOOD LUCK!

[trb]

CARA , That is your main problem you need to fix the REC. MOTOR for your defrost setting to work ( windshield ). If you still have a problem after the repair you should make sure your heater core is not cracked or leaking. GOOD LUCK!

Correct. The Recirc needs to be off for the defroster to work properly. And the AC needs to work too, since that is what pulls the moisture out of the air. On defrost the system cools the air first to remove moisture, then heats it up if you have the temp knob set to heated air. I know when my Mustang's AC was broken, I could never drive it on a humid or cold day without the windows fogging up like crazy.

Good luck!

[vibrologist]

Fix that recirc door motor and you will be fine.

[mr.clutch]

Just a side note...... I don't like to disagree with members so sorry for this. I have heard this said by several people on here but you do not need ac to defrost or defog your windows in a car. The reason your compressor runs when you put your car on defrost is to keep the pump ( compressor ) and seal in the system from drying out through the off season. By the comp. cycling on and off it keeps the oil moving through, seals stay lubed and the system holds the charge. Just think if you need AC cars without air would not be able to clear there windows. DONE SORRY AGAIN. Mike

[trb]

No, I'm sorry, but that is what I've heard, and it did correspond with my personal experience as noted on my Mustang. I dreaded the evenings when it was raining and I had to drive home with partially fogged windows that I could not roll down. It did work somewhat, but I would say at probably 50-60% of how it worked when the AC was operational. It did work better with the heat on, but I didn't really want the heat running constantly on a muggy night!

[vibrologist]

It comes down to the dew point. Defogging requires air that can pick up moisture. Cooled air is dryer than fresh air. This is why A/C makes defogging efficient.
Mr. Clutch is correct too: keeping the oil moving helps keeping the system intact. They caught two birds with one stone.

And if your car is really soggy with dogs and husband and rain wet clothes put on the heat and the A/C and recirculate.