Exhaust gases in heating/A/C systems?

[Apu McRodrigues Ibn Hottab]

Is it possible in theory that exhaust gases to end up in the heater/A/C
ducts?
Is it an unusual problem?
My GF complains that her head starts to ache after she drives with A/C on
for some time...
What would typically be the cause of this? (in terms of the part that is at
fault)

Thanks.

 

[Edward Hayes]

Maybe driving with back window or tail gate open and a tail wind? AC leaking
freon from evaporator? Serious exhaust leak allowing gas to be pulled into
the fresh air vent? Running vehicle with all windows closed and air control
set for recalculation allowing a hi concentration of CO2 in the passenger
compartment will cause head aches and drowsiness. eddie

 

[Richard \(UK\)]

One thing the air-con does is dehumidify the air, and some people find that
a particularly dry atmosphere gives them headaches. My wife suffers from
this side effect when I've had the air-con for some time. - OK?

 

[Edward Hayes]

Right on Richard and I also keep the control off of recalculation so the CO2
does not build up. ed

 

[TM]

How old is her car?

I suffered headaches for about 2 weeks when driving with my A/C on.

At the end of the second week, I took the A/C evaporator fan (the one
that circulates the air inside the car) and found a humongous growth of
mold and fungus in the A/C evaporator coil, not to mention lots of small
rotten tree leaves etc. Heater and A/C air pass through the evaporator.

One growth raised up from one of the evaporator pipes. It was so big i
kept it to show it to my friends so they would not think i was exaggerating.

Cleaned the evaporator with water and a soft brush and got rid of the
problem.

Good luck