Hello everyone,
I almost always drove my 2015 Altima with windows closed & recirculation on but after I started getting sick I took my CO meter with me in my car and one day I noticed that while I was driving with the AC on low, recirculation mode on and windows fully closed the meter showed 14 PPM (Parts per million) carbon monoxide level, I noticed this while going up a hill on a toll-road while the engine was working hard to keep up the speed up the hill. I then immediately opened the window and the CO level dropped to zero within a few seconds which means the CO meter was working properly.
I later found out that if you have AC on low, recirculation mode on and fully closed windows, the carbon monoxide levels would go up to about 6PPM and would quickly rise to >14PPM within 10 minutes of doing any sort of aggressive driving like what is required sometimes to go on an on-ramp in traffic, up a hill, stuff like that.
The type of carbon monoxide meter I used was a Industrial Scientific T40 Rattler.
Anyone else experience something similar or have any ideas?