We bought a new vehicle a few months ago and already get a sour smell from the AC especially on start up. The last truck we had developed this same problem but over a longer time frame, more like 1 year instead of 2 months. The wife claims that every other car she has been in doesn't have this problem.

Does anyone else have this issue with the aircon and how do you stop it from happening?

Stop smoking in the vehicle or make sure you have the air setting turned to fresh instead of recirculate if you are smoking in the vehicle.

(Assuming you smoke - as we always had that problem when I used to smoke in the car.)

Stop smoking in the vehicle or make sure you have the air setting turned to fresh instead of recirculate if you are smoking in the vehicle.

(Assuming you smoke - as we always had that problem when I used to smoke in the car.)

Thanks for the advise but have never smoked in the car. I thought keeping the switch on recirculate instead of fresh may be the reason but my all knowing wife says none of her friends use fresh air and their cars don't have this problem.

Stop smoking in the vehicle or make sure you have the air setting turned to fresh instead of recirculate if you are smoking in the vehicle.

(Assuming you smoke - as we always had that problem when I used to smoke in the car.)

Thanks for the advise but have never smoked in the car. I thought keeping the switch on recirculate instead of fresh may be the reason but my all knowing wife says none of her friends use fresh air and their cars don't have this problem.

Clean the pollution filter on the air condition, maybe there is something inside, can be a mouse or smal rat.

While you've got the filter out, use an aerosol disinfecting spray - something like Lysol, which I've never seen in Issan. Spray on the filter, into the a/c's air intake, and also the exhaust vents in the cabin - where the cold air comes out when you're driving. sorry for the post being slightly disjointed :-(

While you've got the filter out, use an aerosol disinfecting spray - something like Lysol, which I've never seen in Issan. Spray on the filter, into the a/c's air intake, and also the exhaust vents in the cabin - where the cold air comes out when you're driving. sorry for the post being slightly disjointed :-(

I'll give that a try and see if it helps.

The big question for me is why it is happening and what I can do or not do as the case may be to prevent it from happening again

You can probably trace it back to something in the air-con ducts is promoting bacterial growth. It can lead to serious respiratory problems.

While you've got the filter out, use an aerosol disinfecting spray - something like Lysol, which I've never seen in Issan. Spray on the filter, into the a/c's air intake, and also the exhaust vents in the cabin - where the cold air comes out when you're driving. sorry for the post being slightly disjointed :-(

I'll give that a try and see if it helps.

The big question for me is why it is happening and what I can do or not do as the case may be to prevent it from happening again

I have had this happen twice on two different vehicles and a mate had it happen continuously on his pick-up. In all occasions it was small mice that had eaten or managed to get into the ducting and then died. When i took my fortuner to toyota, they knew exactly what the problem would be and told us that they get many vehicles a month through the workshop to repair and or clean the system. We live in the sticks so would expect it to happen more but i know of guys who live in the citys who have had the same problem. Unless you can fully cover the car, i can't really advise a way to prevent it, other than leaving traps near your vehicle whilst its parked at home!

While you've got the filter out, use an aerosol disinfecting spray - something like Lysol, which I've never seen in Issan. Spray on the filter, into the a/c's air intake, and also the exhaust vents in the cabin - where the cold air comes out when you're driving. sorry for the post being slightly disjointed :-(

I'll give that a try and see if it helps.

The big question for me is why it is happening and what I can do or not do as the case may be to prevent it from happening again

I have had this happen twice on two different vehicles and a mate had it happen continuously on his pick-up. In all occasions it was small mice that had eaten or managed to get into the ducting and then died. When i took my fortuner to toyota, they knew exactly what the problem would be and told us that they get many vehicles a month through the workshop to repair and or clean the system. We live in the sticks so would expect it to happen more but i know of guys who live in the citys who have had the same problem. Unless you can fully cover the car, i can't really advise a way to prevent it, other than leaving traps near your vehicle whilst its parked at home!

I will have it taken in and looked at since i can't make heads or tails out of where the AC filter is located. It doesn't seem like dead animal smell just moldy smell that a house AC gets once in a while or more like hotel AC that i have stayed at that have a sour / moldy smell. If it was a small animal the smell would dissipate over time but on my last car it never did go away. I will take it in and have the shop look at it.

Thanks for the replies and anyone with more info please let me know.

Many Jap cars have the air filter behind the glovebox. Remove the glove box. European cars have it outside near the wiper motor under the engine hod on top of the firewall.