Aircon smells like fart after driving in S or S# mode

[iSpecB]

Hi,

Excuse my language but yes, the interior of my my08 3RB does smell like fart after driving in S or S# mode. It doesn't happen all the time but when it does. It causes quite a fair bit of misunderstanding between the passengers in the car as you can imagine...

Brought it in to my local Subaru dealer to have a check but could not replicate the issue and they were scratching their heads as well.

The fart smell comes from the centre Aircon vents when it does happen. I'm puzzled as well as i thought any smell from the engine Compartment should be isolated from the car interior?

Would be great if someone here at this forum could help shed some light. Thanks!

[bigBADbenny]

This may be obvious, but have you checked the AC filter? They get pretty dirty, I swapped mine for a washable, reusable Phat AC filter - which is just great!

[iSpecB]

This may be obvious, but have you checked the AC filter? They get pretty dirty, I swapped mine for a washable, reusable Phat AC filter - which is just great!

Will give it a shot mate. Hopefully it's as simple as this! thanks.

[bigBADbenny]

Let us know how you go. My car went from smelling like musty gum leaves to smelling neutral.
If you search AC, A/C, air conditioner etc, on the forum there's suggestions for avoiding condensation on the filter and so on.
Hopefully it's that and not something worse!

[DeMobBoss]

Smells like a bad elevator joke you say... Hmmm this usually means Hydrogen Sulphide if I'm not mistaken and usually smelt/dealt when the catalytic converter isn't doing its job or due to incomplete combustion of poor quality fuel. Either way never heard of this happening before on these motors.

[Dropz]

does it happen when youve already had the aircon on recently. say drive to the shops, aircon on, go into shops for half hour, come out and bam it smells? cos if so that would be the condensation on the evaporator which is unavoidable. you can get certain sprays which can disinfect and neutralise odours in the a/c vents but theyre never 100%.

[iSpecB]

does it happen when youve already had the aircon on recently. say drive to the shops, aircon on, go into shops for half hour, come out and bam it smells? cos if so that would be the condensation on the evaporator which is unavoidable. you can get certain sprays which can disinfect and neutralise odours in the a/c vents but theyre never 100%.

did more driving over this easter long weekend and found that it's not jsut in S or S#....even in I mode too!

what i had observed is that this happens whenever the engine's been revved to say over the 4000rpm mark...that's when the funny fart smell comes out from the center aircon vents. I also observed that it only happens once and then it stops happening for a few hours (after stopping the car and starting again in a few hours) and then it happens again albeit not as pungent.

so it seems like it's building up this 'fart' somewhere in the car....and I have no idea where it is!!

I don't think it's poor quality fuel either as I've always been pumping it with BP 98 ever since I took over the car 2 weeks ago.

[bigBADbenny]

The clutch is pretty smelly when provoked

Is it dead rodent smell? Was the car stored?

[DeMobBoss]

Sounding more and more bizzare the more details you provide

[iSpecB]

The clutch is pretty smelly when provoked

Is it dead rodent smell? Was the car stored?

it smells exactly like someone's fart...not kidding mate.

it is bizzare....even the head mechanic at my local subaru dealer couldn't tell what's wrong.

the car's not stored, it's just parked in my garage and has been driven almost on a daily basis to work and out.

[bigBADbenny]

Was the car stored for long before you bought it?

I'd work by process of elimination, it's either something mechanical, or organic.
Organic wins because there are related posts here - perhaps a common issue?
So I'd eliminate the organic first by checking/replacing/upgrading the cabin filter.
Then I'd find the A/C condensation cycling post here and fully go through that.
Then... there's more...
Let us know your progress.

[Ric]

I don't think it has been made clear yet. Is your car a manual or an auto?
i.e. do you have a clutch?

[iSpecB]

I don't think it has been made clear yet. Is your car a manual or an auto?
i.e. do you have a clutch?

It's automatic. I've since booked for a free check up with my local Subaru mechanic in 2 weeks time. I've asked for a change of the pollen filter as well. Wll keep you guys updated on this.

[Jaz]

The smell you may be getting sounds like the smell of Sulphur.

It is present in higher levels in Optimax as it's part of the "cleaning agents" they put in the fuel. It's also present in BPs stuff but to a lesser amount.

I'm also led to beleive that you can get a sulphur smell from the head gaskets leaking, but your mechanic should check that, and previous guys should have already.

[iSpecB]

The smell you may be getting sounds like the smell of Sulphur.

It is present in higher levels in Optimax as it's part of the "cleaning agents" they put in the fuel. It's also present in BPs stuff but to a lesser amount.

I'm also led to beleive that you can get a sulphur smell from the head gaskets leaking, but your mechanic should check that, and previous guys should have already.

Ok here's the latest update!! Sent the car to Subaru today and had the head gasket and pollen filter checked...
- head gasket: no leaks! (phew)
- pollen filter: like a piece of sanitary pad soaked in someone's crap!!!! Ok, I exaggerated but the truth is, it was really dirty!

So got it changed and drove my car in S# mode revving it big time and no fart smell!!! Woohoo case closed!!!

Thanks everyone for the replies, hope this helps someone else in the future if they experienced the same. Cheers!