Heater matrix

[barchetta_ms]

I suspect (but not yet confirmed) that I may have a leak in my heater matrix. The car has always had a slightly odd smell and the windscreen always seems to have a film of dirt on the inside. It doesn't appear to use any coolant so any leak would be very minor.

Before I start pulling things apart :
- Has anyone replaced the matrix ?
- I read that the similar age Yaris matrix is the same fit (you would need to swap the pipes) and you can buy a new non-oem one for reasonable money (http://www.motoradsonline.co.uk/products/Toyota-Yaris-Car-Heater-matrix-1999-to-2005.html) - does anyone know if this is correct?
They do look very similar
MR2 - https://www.ebay.co.uk/itm/303862645874?hash=item46bfa00472:g:rSQAAOSwCh1gEW8q
Yaris - https://www.ebay.co.uk/itm/Toyota-Yaris-Heater-Matrix-1999-2005-Models-/265193322612?var=0&mkevt=1&mkcid=1&mkrid=710-53481-19255-0&campid=5338268676&toolid=10044&customid=CjwKCAjwruSHBhAtEiwA_qCppseXTpoEiHQAZgFrfyPGixRYoho5BTQsGBVLU_MhYnTG-LajNCC35hoC8C4QAvD_BwE

thanks

[barchetta_ms]

Just wondering if anyone had any thoughts on this - the smell is worse with the heater on.

[Ardent]

Missed this the 1st time round.

If we are talking smells from the air con only. Before you go ripping things apart.
You may wish to consider trying this first.

https://www.burrowscarparts.co.uk/genuine-toyota-air-conditioning-system-cleaner.html

I have used this on the daily. Lexus CT200 with good results. To the point I may consider it an annual preventative service measure.

[barchetta_ms]

Thanks @Ardent - I did use an aerosol that you release into the cabin previously but will give this one a try too. The smell even lingers on your clothes after you have been in the car.

This thread looked interesting but I can't figure out how anything from the engine bay could get into the cabin with the soft top up/hard top on:

https://www.mr2oc.co.uk/forum/topic/cabin-smell-168290.html?__cf_chl_tk=dIP8__Jc3iZ_ggaCVDfAh_DnE8dzh0Ta8R4elxEIIoU-1668463964-0-gaNycGzNCNE

[Topdownman]

Have you checked under your carpets for any previous water ingress? Once it gets in, it cant get out.

[Carolyn]

If the coolant level is not going down,(Check weekly when the system is cold) then it's not the heater matrix.  Check under the bins to see if there's water there.

[MRSwede]

Are your car equipped with ac ?

Not uncommonly that the smell comes from that system

[barchetta_ms]

I've not seen the coolant drop
I've had the bins out and it's dry in there

I've ordered the AC cleaner (yes it has AC) that @Ardent recommended and will try that.
If that doesn't help I'll pull the carpets up and check under there

Thanks for all your advice so far!

[Joesson]

I've not seen the coolant drop
I've had the bins out and it's dry in there

I've ordered the AC cleaner (yes it has AC) that @Ardent recommended and will try that.
If that doesn't help I'll pull the carpets up and check under there

Thanks for all your advice so far!

In another thread @jvanzyl recently upended a bottle of milk in his car. While he has been fastidious in the clean up maybe the previous owner of your car was not so particular.

[jvanzyl]

You can have the carpet out in just over an hour (possibly less) taking your time... and even less if you're just sticking your nose under it for a sniff...

Or you might be really unlucky and have a hole in your floor and water ingress though there...

[Ardent]

Thanks @Ardent - I did use an aerosol that you release into the cabin

I went to an AC specialist and that's what  they used. Minor if any improvement.
Much better success with this can. The way you use it though, takes a bit of confidence. For a 2. I think 1/2 a can might be enough.

[1979scotte]

You can have the carpet out in just over an hour (possibly less) taking your time... and even less if you're just sticking your nose under it for a sniff...

Or you might be really unlucky and have a hole in your floor and water ingress though there...

There are holes with bungs under there maybe one is missing.