This evening I was driving my 90 Z back from the Dallas Auto Show. Everything was golden until I pulled off the highway and up to a stop light. The idle stayed at about 2000 RPM for 20 seconds or so, then, in steps, dropped to 1200, then 750, then 600 or so where it remained for the rest of the drive home (all on secondary streets). It hasn't done this before, but I really haven't driven it enough to know what is normal. Any comments/suggestions?
Jim