I have a 2002 Camry XLE V6 with the automatic climate control system. Can anyone comment on the dangers of driving extended periods (several hours) with the automatic climate control system set to "auto" and the air source set to re-circulate? By default, the automatic climate control system sets the air source to external (fresh) air. I normally drive in this mode. However, I sometimes set the air source to re-circulate when driving through tunnels or through dusty work zones. On several occasions I have forgotten to set the air source back to fresh air once past the hazard, and continued to drive for several hours with the air source set to re-circulate. I'm concerned about the possible health issues of doing this.
The owner's manual does not have any explicit warnings about driving in this mode, but is it possible for carbon dioxide (from my respiration) to reach toxic levels? I recognize that carbon monoxide from the exhaust system is another potential danger, but my car is well maintained, so perhaps this risk is minimal as long as the car is moving?
When in re-circulate mode, does the Camry's ventilation system allow any fresh air to enter? If not, how much air enters the car via other sources? Searching the web provided the following information, but I don't know how it applies to my Camry since it is quieter (better air seals) than many other cars.
From
Thank you,
--David