An acronym standing for "Phone, Asian, Chick, Elderly," stereotypically considered the four worst categories of drivers (i.e., people talking on
cell phones, people of
Asian decent, women and old people). Similar to a pace car in NASCAR, the PACE car usually sets the pace for the flow of traffic by driving slowly or erratically in front of cars wishing to pass or drive faster. Once the PACE car gets out of the way, traffic will return to normal speeds and predictability. Often other drivers in the rear of the pack will guess which category the PACE car driver belongs to before seeing
the driver when and if they are finally able to pass.