The "NPR "Car Talk" show's "Puzzler" a couple of weeks ago gave an
answer stating that some car's computer "knew" a front tire was low on
air because the ABS system noted that wheel was rotating "a heck of a
lot faster" than the other wheels when the car was driven.

I don't buy it either. I know a GM mechanic and he states there are
sensors in the wheel that transmit tire pressure to the computer.
His bitch is that it complicates simple things like rotating
tires because now he has to connect the scan tool and tell the
computer how he rotated the tires.

cs