Car badly misting up, really badly.

[TOXIC]

As per title, my IS250 is a nightmare for misting up inside and it’s driving me mad. No sign of damp or leaks anywhere and I’m not losing coolant, no smell of damp either.

The aircon has got a leak as I was told in the summer when I went to get it regassed but I don’t think that is the issue?

It makes no difference where I set the heating controls to hot, cold outside air in or to recirculate the car mists up like crazy.

Now I was advised to change the pollen filter which I will do, but removing the filter it was pretty much spotless although I’ll replace it anyway. What I did notice when changing it however was that it didn’t move at all when I changed the heating from outside to recirculate, the filter stayed put.

 

Could this be the issue?

[NemesisUK]

Firstly I'd get the a/c problem sorted. The a/c does a good job of dehydrating the air within the cabin and really does stop the windows misting up. I leave my climate controls set to auto everything with a/c on.

I'm not 100% on this but IIRC when removing the pollen (cabin) filter one must have the re-circulation flap set in the open(?) position, otherwise one can cause it to fault and not work correctly. Hopefully someone more knowledgeable will clarify that last bit!

[johnatg]

Mine misted up all the time I had it. 

You must not set the air con to outside when working on the pollen filter - you may have a broken door to it. 

Unlikely to be connected with misting

I alleviated the problem with silica gel - you can buy it in a large pack and stuff some old socks with it. Dry on a radiator or in a microwave. 

[J Henderson]

Clean glass is paramount. Dirty windows are more prone to misting up or taking longer to clear up. I notice this all the time driving different work vehicles.

Like Nemesis, I leave the climate control set to Auto, with A/C on all the time.

At this time of year, I also keep one of those dehumidifying bean bags in the car. I position it on the transmission tunnel, so I'm not sure how effective it is placed down there but I just view it as a passive measure that can only help.

 

[TOXIC]

I’ve got two dehumidifiers in the rear of the car and they bushes made no difference.

When I went to remove the filter I made sure the heating/venting was set to recirculated and I also set it to outside and circled between the two but the shutter that would prevent you from accessing the filter when it’s set to draw air in from outside didn’t operate.

Could this at least be part of the problem?

Ive also noticed that the front side vents to the passenger and drivers side windows are pathetically weak, coild this be related to the flap that’s supposed to close when the car is set to draw air from outside?

 

[normski2]

15 hours ago, TOXIC said:

 

When I went to remove the filter I made sure the heating/venting was set to recirculated and I also set it to outside and circled between the two but the shutter that would prevent you from accessing the filter when it’s set to draw air in from outside didn’t operate.

 

 

This does sound like the actuator lever has been broken as the lid on the filter will lift up when set to 'Recirculate'.

There was a repair procedure put up on the USA Lexus forum. I'll go see if I can find it. Its not too complicated if you are at all handy at having a go.

Like others have said I too leave my A/C on and set to 'Auto' permanently. Never ever had any misting of windows in 8 years ownership.

[TOXIC]

6 minutes ago, normski2 said:

This does sound like the actuator lever has been broken as the lid on the filter will lift up when set to 'Recirculate'.

There was a repair procedure put up on the USA Lexus forum. I'll go see if I can find it. Its not too complicated if you are at all handy at having a go.

Like others have said I too leave my A/C on and set to 'Auto' permanently. Never ever had any misting of windows in 8 years ownership.

Thank you, if you could find the link for the repair that would be much appreciated.

[normski2]

Found it!!

Have a good read thru this from first to last post. I can vouch for the JB Weld (2 pack bonding/repair glue) as being most excellent for other repairs I have undertaken. You can get it from eBay.

Link

Hope that helps you and good luck with it.

 

[normski2]

Take a good look at the pictures shown and take a look at yours and see if you can see any breakages anywhere.

[TOXIC]

22 hours ago, normski2 said:

Take a good look at the pictures shown and take a look at yours and see if you can see any breakages anywhere.

The link isn't working for me i'm afraid?

[normski2]

Sorry about that I should have checked after inserting the link. Try this

https://www.clublexus.com/forums/is-2nd-gen-2006-2013/612326-diy-for-an-oops-moment-tried-to-replace-cabin-air-filter-without-setting-to-circ.html

Copy and paste into your browser

[normski2]

Actually, you can just click on it .. that worked for me just now!

[TOXIC]

On 11/17/2021 at 4:04 PM, normski2 said:

Actually, you can just click on it .. that worked for me just now!

I've just read through that entire thread, excellent post and thanks again.

I was wondering however, if it would be possible to just reach in and pull the cover down manually from inside the glovebox to do for the meantime?

I know it's most likely a case of just try it and see but thought I'd ask and see if anyone else that had done this repair before would know.