I'm getting this weird sulfure-like smell when I turn on my heating/cooling ventilation system. It only goes away when I turn on the A/C mode. Anyone have any clue how to get rid of this smell or where it is coming from? Will replacing my in-cabin air filter get rid of this smell?

bump...

I couldn't tell you what it is. I know every so often my car smells like a rotten egg when I drive around hard. It's just the catalytic converter getting all the crap out. That might be what it is. I would like some time pass to see if it goes away.

yeah, mine smells every so often, whether i push it hard or not. i think there might be a leak in my ventilation system...

My girlfriends car(2000 Camry), just started smelling like vinegar when the A/C is turned on....kinda weird and have on clue what's causing it.

haha for the people who said vinegar and rotten eggs did it ever occur you might have enemies????????

As for the air filter I dont think that will do anything since my car has 46,000 miles and I havent changed mine due to weird smells, but you should check all your piping make sure nothing was coming in contact with a heat source.

change the cabin air filter....
its recommended every 15k anyway

your cat is on the way out. if its stock then it should be covered under warranty. if not, then spend the money on a test pipe, problem solved.

It is the air conditioner. Comes from the refrigerant change, in the late 90's. The new R -134a has the rotten egg smell. It will not go away. Best thing to do, is to turn off the A/C in the last mile and run outside air, before turning off the engine.
You could spray in freshener from the outside vents into and ventilate it throughout your ducts. The product for A/C is call Fresh air and is about $15 to $25 a can, but I use disinfections spray.
And it is not your Catalytic! Don't bother changing the cabin filter. The smelly gas is too fine of particle.

Does your girlfriend have gas?

Sounds like you guys need to replace your cabin air filters, it is right behind the glovebox.

yeah, it's weird. i only get the smell when i turn the A/C off and use outside air. when i turn the A/C on, the smell goes away after a bit...

Maybe the easter bunny hid some eggs in there and they went bad.

ya defi the catalytic converter i bet.