T27 windscreen misting

[Brn]

Hi Folks,

I feel, that in my 2010 T27 estate 1.8 petrol the windscreen fogs up to much and too often and clears very slow. I would like to gauge what it is like for other owners, before starting to look for faults and leaks. It has the dual zone climate control option.

Yes, unfortunately we have to use it for short school runs more often than I can avoid feeling guilty about it. (But need to work as well, so walking cycling is not always an option)

A/C does clear the windscreen on the demist function after 4-5 minutes idling on a chilli, 4-10 degrees, humid morning with the windows cracked open. Is this normal demist speed or slow?

Then, when the engine or the A/C is switched off, the windscreen starts fogging up. Is this normal or indicative of a fault (blocked a/c drain?) or a leak into the car?

(I do miss the heated windscreen of my previous car, but I don't miss the distorted night visibility it gave.)

 

[DerekHa]

Hi Barna,

Is the blower motor functioning as it should?

Have had similar problems in the past with various vehicles. Would think in general if the misting is as much of a problem as you descibe then you could have water lying somewhere in the vehicle. Check around for damp/wet carpets in the footwells and also check the cargo area being  as you have an estate, along with the spare wheel well if you have one.

Also worth checking that your A/C cabin filter isn't blocked or even water logged. Another avenue you could investigate is the rear air vents, if they are blocked or not working properly they can stop the moisture laden air inside the cabin being vented out from the interior of the car.

[Derek.w]

For best results you need the a/c on to stop if foging up plus direct airflow to windows then when clear leav a/c on and redirect airflow to cabin if needed.

If you turn a/c off its starts fogging up again.

[2009joe]

i have this problem  with my 2014 avensis compared to my last car not sure why in the t27 it fogs up more so 

[DerekHa]

I have never owned an Avensis so can't comment on it's characteristics.

I have a little Skoda Citigo with A/C. It never gets misted or fogged up to any real degree and if it does during this colder weather I don't have the A/C on to clear it, It's not climate controlled though. Seems to be a false economy to me using A/C during the colder months of the year when standard interior heating will work fine. Using A/C anytime of the year will drop your MPG by probably 10%. An exprensive game given the cost of fuel now.

Not knocking anybody's advice just expressing my opion. Definately agree on opening windows to let the moist air out when the glass starts to clear.

[2009joe]

22 minutes ago, DerekHa said:

I have never owned an Avensis so can't comment on it's characteristics.

I have a little Skoda Citigo with A/C. It never gets misted or fogged up to any real degree and if it does during this colder weather I don't have the A/C on to clear it, It's not climate controlled though. Seems to be a false economy to me using A/C during the colder months of the year when standard interior heating will work fine. Using A/C anytime of the year will drop your MPG by probably 10%. An exprensive game given the cost of fuel now.

Not knocking anybody's advice just expressing my opion. Definately agree on opening windows to let the moist air out when the glass starts to clear.

do you even own a toyota at all 😉  maybe you are on here because you really want to own a die hard toyota the  one and only brand to buy :)

[DerekHa]

*****

[DerekHa]

21 minutes ago, 2009joe said:

do you even own a toyota at all 😉  maybe you are on here because you really want to own a die hard toyota the  one and only brand to buy 🙂

Try again!

Your remark comes across as a little condescending or even rude.

You no what they say Joe? Oranges aren't the only fruit, variety's the spice of life they say also!

We're all here to share and help and benefit from the knowledge of those who have it.

[2009joe]

40 minutes ago, DerekHa said:

Try again!

Your remark comes across as a little condescending or even rude.

You no what they say Joe? Oranges aren't the only fruit, variety's the spice of life they say also!

We're all here to share and help and benefit from the knowledge of those who have it.

all  good bud nothing bad meant my bad buddy only joking boss my bad if u thought that .only saying toyota is the one and only car to own i guess 

[DerekHa]

2 minutes ago, 2009joe said:

all  good bud nothing bad meant my bad buddy only joking boss my bad if u thought that .only saying toyota is the one and only car to own i guess 

Yes ok Buddy, me old pal. Least said soonest mended as my Da" used to say. 🙂👍

[JARC1]

Had this constant misting (especially in damp weather) with my 2012 Gen 3 Avensis. The advice about constant AC is good. I keep my AC running at all times and no more misting for me.

Regards, John

[FROSTYBALLS]

Using air con in conjunction with the heater is an established method of demisting quickly, as the air con provides dehumidified air. 

I first learned about this back in 1998 when collecting a new Primera, and have used it ever since.

See also: 

If you think there has been a build up of moisture in the car, you can get dehumidifier bags from Amazon, etc, which can help absorb excess moisture in the car, if left in there for a couple of days of so.

[DerekHa]

Ah, I see the reasoning now.

45 minutes ago, FROSTYBALLS said:

Using air con in conjunction with the heater is an established method of demisting quickly, as the air con provides dehumidified air. 

I first learned about this back in 1998 when collecting a new Primera, and have used it ever since.

See also: 

If you think there has been a build up of moisture in the car, you can get dehumidifier bags from Amazon, etc, which can help absorb excess moisture in the car, if left in there for a couple of days of so.

Ah I see the reasoning now.

Agree that excessive moisture inside the car needs to be mopped up and those bags sound ideal.

[MrAurisT]

The simple answer to your question is yes! I have a 2010 1.8 TR estate and from day 1 its windscreen misting up abilities never cease to amaze me LOL. As above, the windscreen demist function does work, but, generally, I make sure the vent is screen/feet then blast the fan for 60 seconds or so. As I have a large (usually wet) large Labrador in the boot often, I always, weather allowing, leave the rear hatch/boot lid up to 'air' the car for a few hours when I can. I don't think there are any leaks or similar with my car its just one of the quirks I have learnt to live with.

[avetoy]

17 hours ago, Brn said:

I feel, that in my 2010 T27 estate 1.8 petrol the windscreen fogs up to much and too often and clears very slow. I would like to gauge what it is like for other owners, before starting to look for faults and leaks. It has the dual zone climate control option.

I have similar (2009) Avensis and never have had that kind of problem... What about other glasses, are they fogged too?

Could it be possible that the heating device has internal circulation on?

[Brn]

Thanks for the responses fellas.

To answer some points posted above:

The car has the demist function, which when activated, blows all air on the windscreen/front side windows at full speed, turns the A/C and internal circulation on. As said before, I also crack the windows open as well to let the moist air escape. (See here for scientific explanation

)

We don't run the internal circulation unless necessary.

All other glass fogs up as well, but i guess windscreen being the largest, it will cool down quicker and heat up slower.

The blower motor is fine and it is actually right below the cabin filter, so that would make sense to cause problems if wet, but I have checked and it is dry.

I also leave windows down in hot/mild weather, because I know that otherwise I'll experience horrible misting up.

We have tried dehumidifying bags in the past, but didn't notice any difference TBH.

As some other Avensis owners also have similar problems, it could be just a thing to live with. I'm not sold on switching to a Skoda yet. 😉Maybe I'll also join the Skoda owners forum.

Could water get in past the external window seals? Mine are are quite brittle and frayed. Anyone else's like these? Or do the doors drain to the outside, so that water shouldn't get in?

Does someone know the location of the A/C drain? I might want to check if it is accessible.

[avetoy]

Is there any odd smell inside the car? For examble: if the heater coil is leaking, there is kind of sweet smell... and the windscreen sure gets misty!

[Brn]

6 minutes ago, avetoy said:

Is there any odd smell inside the car? For examble: if the heater coil is leaking, there is kind of sweet smell... and the windscreen sure gets misty!

I have thought about that, but I am not loosing coolant and there is no coolant smell.

[avetoy]

53 minutes ago, Brn said:

The blower motor is fine and it is actually right below the cabin filter, so that would make sense to cause problems if wet, but I have checked and it is dry.

Would it be possible that the air access from the outside was somehow blocked? Even though the filter is clean.

[MrAurisT]

Plus one for the cracked/brittle/frayed window seals as well....our cars must be twins!

[Brn]

On 11/28/2022 at 5:12 PM, avetoy said:

Would it be possible that the air access from the outside was somehow blocked? Even though the filter is clean.

Yes, that's a good idea. Wet debris, dust, plant matter maybe blocking or partially blocking the air inlet and making the system constantly suck moist air in...

[Brn]

On 11/28/2022 at 5:51 PM, NeilAvensisT said:

Plus one for the cracked/brittle/frayed window seals as well....our cars must be twins!

Hmmm...

Are the windows seals supposed to press against the windows on the inside or the outside or both? Mines seem to touch more on the inside and in patches on the outside.

[Brn]

I have searched om YouTube and based on Yaris and Prius videos, yhe AC drain pipe should be in the footwell somewhere... Anyone with more details?

[avetoy]

One more possibility are the interior air exhaust flaps at the back. If they don´t work ventilation won´t work either (moist air can´t get out).

[DerekHa]

54 minutes ago, avetoy said:

One more possibility are the interior air exhaust flaps at the back. If they don´t work ventilation won´t work either (moist air can´t get out).

Agree with that! One of the suggestions I made back on Sunday on this topic but I'm only a mere Skoda owner. 🙄