When I first switch on my car, the air con has a bit of a bad smell just for a few seconds.

I understand this is because of bacteria/fungus growing in the air con system.

I took the car to Honda for its service and asked them if they could fix this as I read here that a spray should easily do the job.

Their answer was that the paper filter was very clean and that the smell was caused by perfume from my air freshener (little bottle of liquid attached to the vent) being trapped in the air con system.

Can wiser heads here please advise if this sounds right?

If a spray can do the job, can anyone advise where to buy and how to do?

Cheers!!!!

if it comes from bacteria/fungi , my guess is, that you leave the Air con on, till you stop the car, right?

Try it with switching the aircon of, some minutes, before you stop the engine and the fan.

This way, the condensing water has a chance, to get blown away.

No bacterias, no mosquito breading

There's a product called AtmosKlear that is one of the few products that actually solves the odor problem rather than mask it. I could not find out it's availability in Thailand. In the USA, it's often sold at car dealers. Auto air conditioners and pet odors are two of its primary uses.

Some of the auto detail centers have ozone generators.

Couple of years ago I forgot 1kg minced pork in the car, after the weekend the car smelled extremely. The ozone treatment neutralized the odor completely.

Takes a couple of hours and A/C must running on recirculate during the treatment, ozone works best in cool, dry air.