Questionable funk from the air vents

[SilverBack]

Originally Posted by CTScott

Check the TSB on HVAC evaporator drain blockage:

http://www.yarisworld.com/forums/showthread.php?t=9753

When the drain tube is plugged up the condensate stays in and gets really funky after a while. It happened on my Xterra and I unplugged it from below by sticking a piece of flexible plastic up the evaporator drain tube. When I pulled the plastic rod out, about a gallon of putrid water came gushing out all over me. I nearly lost my lunch...

I'll have a look at it today. Thanks for the much needed info

Quick question: Convinced this isn't a one-time thing, so how often do I need to do this?