I was inspecting the spark plugs on my wife's 92 Sentra XE 5-speed (GA16DE) yesterday and all four of the Autolites in there had dark pink deposits on them. I've never seen deposits in that color, and neither has anybody else I've talked to. My only theories are:
1) funky gasoline additives (which makes no sense since we buy our gas at the same places and my plugs aren't pink.)

2) Some sort of dye coming off the air filter element, which is colored orange.