Fellow Techs, Subject:1989 Buick Regal,3.1L,4spd auto,air,cruise. Problem: Tip in Hesitation, slight miss low RPM low-med load(45-55 mph 4th & lockup) Resent tuneup(plugs,fuel filter,air filter),throttle plates cleaned. Scoped-looked good,scanned-no codes data... Login to read more.