stuffy cabin air

[dach2k3]

Something is up with the cabin air in my car. it has about 5,200 miles on it and it smells stinky when the AC first comes on. I made an appt for service, but was wondering if anyone had any thoughts. I checked the cabin air filter and there were no leaves caught in it. I am wondering if there is any other likely place for leaves or something else to get caught in.

 

[CanukV6]

I assume you aren't running with the 'Recirculating' function on, in which case the most likely cause is a blocked drain somewhere causing moisture build-up inside the A/C system.

 

[dach2k3]

i tend to switch back and forth between recirculate and intake.. depends on outdoor smells. But it gets good use both ways. A blocked drain might seem likely. I would of thought it was something caught somewhere that was decomposing some.

 

[Alwaysforward]

Clogged drain line as noted above. When you locate it, please let us all know where it is located. If I remember I will look under my car to see where the condensation drips out below the car.

 

[Gunkk]

Mold grows at 70% RH and above, or in standing water when any organic matter (dust) is present. If you have ever had people in your car, then there is dust in your car's ductwork.

Living in the swamp, I have found it's better to keep the air either full time recirc, or full time fresh air. Switching from fresh to recirc is OK. But switching from recirc to fresh is bad if the system has been running.

Here's why: When you use recirc, the cabin air gets very dry and ductwork cools way down. When you suddenly move to fresh, you pull in lots of humid air, which may not all condense on the evaporator coil. What gets by the coil sometimes shows as a mist coming out of your vents, but definitely will condense on the inside walls of the ductwork. Then mold/mildew/etc. grow in your ductwork, especially if the duct is shaped such that it cannot drain back to the evaporator chamber and down the drain pipe, or you live in humid climate and like to park in the shade where the HVAC system will never get a chance to dry out on it's own or bake-out in the sun.

If you do insist on using fresh air, say for cooling the car rapidly after sitting in the hot sun, or to avoid the sleepies on a long drive, then switch back from fresh to recirc a few minutes before you end your drive. This will help dry out the ductwork and dry the air inside the car.

Some cars and makes are better than others due to system design and choice of materials. My old Toyota 4Runner was horrible with this, even with full-time recirc and sitting in the sun. My wive's solara is not much better. My Honda accords were perhaps the best, and my 09 and 12 Gennies were/are better than average.

Your dealer's service department can remove the cabin air filter, and run the system while spraying some HVAC disinfectant into the intake to kill off the beasties. This should fall under the 12-month "adjustments" warranty.


Bottom line: to avoid the Primordial_Ooze_in_the_HVAC problem, always use recirc.

 

[dach2k3]

Thanks for the explanation. That makes sense. I live in Miami, so it is plenty humid, especially the last 2 months.

I will adjust my habits.

I remember a long time ago having someone explain to me why recirc all the time was bad but i cannot remember the reason.

Thanks.

 

[Mark_888]

Thanks for the explanation. That makes sense. I live in Miami, so it is plenty humid, especially the last 2 months.

I will adjust my habits.

I remember a long time ago having someone explain to me why recirc all the time was bad but i cannot remember the reason.

Thanks.

Probably the main reason is that over time (due to humans in the cabin), the oxygen content on the air decreases and carbon monoxide level increases when the same air is recirculated. This can be a problem depending on the number of passengers and length of trip, since it can make the driver feel sleepy resulting in a safety issue. The Genesis 5.0 Ultimate has a CO2 detector to help alert one to problems if the CO2 level gets too high. BTW, CO2 detectors are recommended for homes, especially if they are reasonably air tight and there are any fireplaces or gas appliances (water heater, range, clothes dryer, etc).

 

[Midnightsun]

Probably the main reason is that over time (due to humans in the cabin), the oxygen content on the air decreases and carbon monoxide level increases when the same air is recirculated. This can be a problem depending on the number of passengers and length of trip, since it can make the driver feel sleepy resulting in a safety issue. The Genesis 5.0 Ultimate has a CO2 detector to help alert one to problems if the CO2 level gets too high. BTW, CO2 detectors are recommended for homes, especially if they are reasonably air tight and there are any fireplaces or gas appliances (water heater, range, clothes dryer, etc).

I think you got your CO's confused as the home variety from combustibles is of the deadly CO and not CO2 which is what we exhale. Just to make it clear, the Genesis detects CO2 (human exhaled air) and not CO (deadly stuff from the tailpipe).

 

[Mark_888]

I think you got your CO's confused as the home variety from combustibles is of the deadly CO and not CO2 which is what we exhale.

You are correct. My mistake.