Chrysler Repair: poor heat, dodge dynasty, head gasket

Question
ok, i changed thermastat and the heat is still irratic. i mean it does get hot but when sitting at an idle the heat becomes less hot. when u accelerate or rev engine it seems to get hotter. i have noticed the temp gauge going all the way to hot, but it does come down. i have checked-the inside of car for wettness but nothing. could it be radiator, water pump or do you have any suggestions.

james------------------------
Followup To
Question -
heat is not as hot as it once was on my 89 dodge dynasty. today (3-22-04) changed thermostat but heat still not like it use to be. could it be the temp sending unit, would that have anything to do with the lack of heat. temp gage inside car never says car is overheating, but does go high sometimes but then drops back down. any ideas would be helpful

thanks, james
Answer -
hello james
the idile as nothing to do with it but that is a bad idile controll senser. and i would change the heater core for heat pete

Answer
hello james
now this is not good at all it is not a rad. if and if the floor is not wet then if the heat goes up and down then it is the starting of a bad head gasket. i would get a pressuier test at a good shop . good luck to you and if i can help you out anymore let me know pete