306 - Nasty smell when switching on air vents ...

Q4Legend · Post by **Q4Legend** » 01 Oct 2004, 16:17

Hi,
I have noticed recently that when I switch the heaters on (air vents) on my N reg 306, there's an awful smell that lasts around 10 seconds.
It does seem to clear after a while and is more noticable when the dial is set to warm.
However, I have a baby and am worried that there could be gases/fumes that may harm her (and anyone else).
Any suggestions?
TIA

Homer · Post by **Homer** » 01 Oct 2004, 17:26

What is the smell like? Is it a mouldy damp smell or a chemichal antifreeze smell?
If it's smelling a little damp and you have air conditioning then it is caused by bacteria (mould) growing in the ducts and there are treatments available for it.
If it smells of antifreeze then your heater matrix has gone, check for damp carpets in the footwell. Replacing the heater matrix is probably a major dashboard out job. Unfortunately it is all too common on Peugot and Citroen cars.

Q4Legend · Post by **Q4Legend** » 01 Oct 2004, 18:09

Thanks for the swift reply....
The smell isn't like mould or anti-freeze - it's more like a kinda burning smell.
Burned oil perhaps?
Crikey, I'm getting worried just writing about it.
Is it just the engine I can smell and why does it go away after a several seconds?
TIA

Stuart McB · Post by **Stuart McB** » 01 Oct 2004, 20:37

Has the pollen filter been changed lately? Could be a that some thing has gotten into the filter housing and is starting to decay, mouse or large instect.

Q4Legend · Post by **Q4Legend** » 04 Oct 2004, 20:10

Hey, that's a good idea mate - I don't believe it has been changed in a long time!!
I'll try that shortly and let you know how it goes.
Thanks for the input m8
GREATLY appreciated

Q4Legend

moomin · Post by **moomin** » 04 Oct 2004, 23:14

if its a burning smell that only lasts a few seconds its probable just dust thats accumulated on the heater burning off.

Q4Legend · Post by **Q4Legend** » 15 Nov 2004, 18:13

Please help - this problem is still persisting.
The smell is definitely a burned oil smell and is more noticable when switching to HOT.
The smell doesn't go away now though which means that I can't use the heaters - typical, as Winter is almost upon us.
The only time I use the blower now is to de-mist the windows and the smell is quite overpowering.
Any ideas?
Please help, cheers

solara · Post by **solara** » 15 Nov 2004, 18:22

Does the smell only come on with fan operation?
Check your ballast resistor pack, it may be smoking with fan motor operation.
It is below the plastic air vent grill beneath the windscreen.
Alternatively you could remove top glove box enclosure and have a sniff behind there, to see if its the culprit..

Q4Legend · Post by **Q4Legend** » 15 Nov 2004, 18:28

Hey, thanks for the swift reply

Yes, the smell is only noticable when the blower is activated. It's not too bad when blowing cold (but definitely noticable) and seems to worsen when the heat increases.
Weird thing is the heater itself is otherwise working great.
How would I get to the ballast resistor pack to investigate and how do I remove the glove box enclosure?
Thanks

beezer · Post by **beezer** » 15 Nov 2004, 19:12

If the ballast resistor pack is burning it will be a very acrid smell. Oil like smell does suggest to me that you have oil on the heater matrix which is burning off and becomes noticable with the blower blasting it through. I would have thought an overheating resistor pack would have cause an erratic fan speed by now. It is a case of training your nose!

arry_b · Post by **arry_b** » 15 Nov 2004, 21:05

Are you sure it's a burning oil smell. Does it have a "curry" tinge to the smell?
My money is on the heater matrix if it does smell like that.

beezer · Post by **beezer** » 15 Nov 2004, 21:11

You must go to some pretty dodgy curry houses arry b! Maybe they are using Castrol instead of ghee.

Stuart McB · Post by **Stuart McB** » 15 Nov 2004, 23:56

Could be the grease in the heater fan bearings. When hot you get the smell but when on cold the cold air may cool it enough not to smell. Failing that is the cold ait pipping to the heater all intact. Could it be broken and allowing engine bay smells in to the car?

solara · Post by **solara** » 18 Nov 2004, 14:22

I remember seeing the ballast pack, the last time I took my dash out to swap the heater matrix http://uk.pg.photos.yahoo.com/ph/solara ... .dir=/de47.
Dont worry you dont need to take your dash out to get to the ballast pack.
I cant remember which side of the bulkhead it was physically located, but you can see it from both sides, as it sits on the intake vent. For engine side of bulkhead, remove the plastic window wiper drainage cover (as decribed in haynes manual). For passenger compartment, remove the upper glove box (if you dont have airbag there) inner compartment. From ther is the main air intake to the heater matrix. Pop that off and you should see the ballast resitor pack. I think it makes sense for it to be on the passenger side of the bulkhead. Should be in the haynes manual anyway.