2002 sporty orginal owner,all orginal,135,000 miles.....she is running great but after going like twenty miles she creeps towards the 3/4 hot mark and i turn on the heater fan to 3 or 4 and she cools right down to half way mark...running heater fan on two mostly keeps her cool unless pulling big hill...my multi tester showed 190degrees at 3/4 mark..... i have seen it go past 3/4 mark but heater fan cools it down quick,,,but i fear i will forget and let her overheat,,,,,,,,it seems to take like 5 more mintues to warm up........any ideas or trouble shoots,,thanks in advance..........