Intermittent Smell From Heater/ventilation System

[Martin1954]

Hi -I have a 2008 (58plate) 2ltr D4D TR Avensis.

Every so often a smell comes into the cabin, apparently from the heater/ventilation system.

It doesn't quite smell like burning, but can be hard on the breathing bits!

There doesn't seem to be any rhyme or reason for this - it comes and goes at will.

Any suggestions what it could be, or what I need too check/get checked.

Thanks

[junebug1701]

When you first notice the smell coming on, change your aircon to fresh air. If you run it too much on recirculate, you will eventually get a musty stale smell. The system needs to be run on fresh at least half the time in my opinion. Also check your cabin air filter. It may need changing--a simple task.

[dervdave]

Has your car a DPF because they can smell pretty bad when they are regenerating and the odour can come into the car.

Its a burning rubber type smell ?

[Jas16]

I think it is something related to the air con. If you can, go to a dealer and there is something specific they do to 'sterilise' the vents, as a friend of mine was getting head aches when using his air con, and after servicing the head aches went. But this was a Hyundai i30, but I would guess that the basic principles stayed the same. Or before you go, talk to a dealer over the phone

[ooarrlatvian]

I have exactly the same thing! Only started recently. I was trying to remember where I knew the smell from and one day it dawned on me that it's exactly the same smell as when my Dyson vacuum cleaner gets jammed up on something like a shoelace and the belt slips causing friction heat.

It's embarrassing when people are with you isn't it!

[MrMez2309]

Had a similar problem on my 2.2 D-4D. Bought a can of Autoglyn Air con sanitizer off eBay. Followed instructions. Worked a treat. Less than a tenner.

[Martin1954]

Thanks all - As with all things mechanical/electrical, it hasn't done it since.

But for the previous replies:

No it doesn't smell like burning rubber & I usually have the controls on fresh air, not recirculate. Only ever use that to either warm the car interior up quicker, or to stop smoke/nasty smells from coming in from outside the car.

If it does it again, I might try some of that Air con sanitizer from Autoglym. Cheers.

[Tyfan]

My Avensis 2l D4D TR Estate 58plate has this problem. After startup, with vent system on Auto, not on recirculate,or Aircon, it gives off this smell. Described above as almost a burning but like a vacuum cleaner belt slipping and heating up. This only lasts a few minutes then vanishes. Really catches the throat. Have tried aircon cleaner which was fine for a couple of days, then back it came. The Dealer has suggested that the problem could be the heater matrix having plastic melted on it. Anyway it is going in at the end of the month for investigation and matrix change. Thank goodness it's under warranty as they quote a couple of days for the job. I will let you know what happens.

4 May

Just got the car back today. They checked out over 2 days all possibles. From a leak onto exhaust manifold downpipe overnight to all pipes and connections from fuel,oil,coolant, aircon etc. The heater matrix clear and filters good. The funny thing is, that for the last fortnight, since the weather has warmed up slightly, the smell first thing is now intermittent. i.e. not every morning on startup.and not so intense. It looks as though I will have to keep an eye on this and see what happens when winter sets in and the temperatures drop again. Luckily it has a years warranty which doesn't run out till Feb. next year. At least, from my point of view, I have been assured there are no leaks or possible fire risks etc. which cant be bad. Will update if anything else happens.

[BigMo82]

Does the air from the vents not go through the pollen filter? If so could that being dirty be causing the smell?

Mo

[mrpj]

Re the sanitiser process.

I've never used one but read that after use there is a residue deposited all over the interior which shows, particularly on plastic trim, and needs to be wiped off. Is this correct or just that it hasn't been used properly?

[Druid Boy]

I did an aircon clean using a can just recently. All it left behind was a nice smell that lasted about a week. After about another week the mouldy aircon smell returned very slightly. I may give it another go as its only been done once after 100k miles.....

[klivey]

i have this foul smell coming through the ventilation/heating system when turned on,can anyone tell me what can be causing this?

[FROSTYBALLS]

Check the air conditioning filter (pollen filter) and replace if dirty. Probably need to have the air conditioning cleaned/disinfected. One can either have the system cleaned at a dealer or garage, or one could buy a product similar to one of the following: https://www.amazon.co.uk/s/ref=nb_sb_noss_2?url=search-alias%3Daps&field-keywords=Air+con+cleaner

[Druid Boy]

I now use a combination of the in-car aircon bomb treatment every 6 months or so and in between I use the spray can cleaner into the air inlets on the outside of the car every 6-8 weeks (I planned to do it each month but keep forgetting).  The spray seems to be very effective at keeping the smell under control.  I will continue with the bombs also just to keep on top of things.