I suppose I knew that academically at least -- I did read that so much fuel condenses onto the manifold at -40 degrees that the computer commands for enough fuel for a 2:1 (yes *2* to 1!) mixture at the throttle body.Perhaps what caddyman was meaning is that if you stick the sniffer of the two gas infrared machine that we used in 1980 into the tailpipe of a 2010 you will be hard pressed to see the needles move. Now if you sniff a modern car with a 5 gas analyzer you could get (I say could as all my sniffing was done in the early 2 gas years) readings that are of value. This 5 gas machine would go beserk if stuck in the tailpipe of a 1980 vehicle, unless the correct scale was selected.
The two gas machines had a gross and a fine scale and I bet the fine scale could not detect a car of today.