<VV> CO Question

[BobHelt at aol.com]

In a message dated 3/7/2010 12:10:04 P.M. US Mountain Standard Time,  
rodneyspooner at corvairgarage.com writes:

How  far is the exhaust pipe sticking out from under the car? I imagine  
that
while the car is idling while parked or slow in traffic, that the  Corvair
exhaust is being re-circulated through the engine's blower fan and  perhaps
being forced through gaps in the heater vents. Don't know why CO  levels
might decrease by turning the heater on other than to speculate that  it 
adds
more air and pressurizes the cabin slightly and also circulates the  CO past
the CO alarm and out the gaps in the window seals instead of the  gas laying
stagnate and denser on the floor. Isn't carbon monoxide heavier  than air?
 
You know of course that all exhaust pipes should be angled away from the  
vehicle into the air stream passing by the sides of the car. No exhaust pipe  
should extend directly back from the vehicle where the exhaust can be 
sucked  into the air intakes.
Regards,
Bob Helt