A friend of mine and myself have been pondering something lately: why is it that car air conditioning smells so bad after you turn it off? Every car we’ve tested, from Ford Escort to BMW 740iL is a culprit. For Pete’s sake, it’s the 21st century… so we don’t have the flying cars yet (I’m still kinda pissed about that one), but you’d think we’d be able to fix a mass problem like this by now.
What gives?
Thanks!
Alternati
Do you mean that immediately upon switching the AC off, you notice a foul odor? If so, sorry…can’t help you.
If, however, you mean that you notice an odor in vehicles in which the AC is used frequently, I may have an explanation.
The cold air flowing through the ducts/vents causes condensation. The moisture that accumulates allows for bacteria growth and…voila…stink.
Many manufacturers advise that you should allow the fan associated with the vehicles ventilation system to run for a short time after switching the AC off. The resulting circulation of air allows any trapped moisture to evaporate.
This has been covered, um, ad nauseam.
Start your car’s engine, turn on the A/C, lower the windows, and spray a 10-second burst of Lysol into the air intake vents located next to the windshield. Repeat as necessary. Drive with windows down to prevent asphyxiation.
This is best done on a mild day.
This procedure will kill off the bacteria in your A/C. Some cars are more prone to this problem and may require yearly treatment.
Look under your hood; there’ll be a short hose, probably L-shaped, coming out of the firewall on the passenger side, pointing downwards toward the ground. This hose drains away the water that collects when you use your AC. If it’s plugged, the water stays in the AC unit, things grow in it, and you got your basic miniature swamp, complete with smell.