Chrysler Repair: chrysler cirrus 2000, chrysler cirrus 2000, chrysler cirrus

Question
my car doesn't actually overheat, but the coolant reservoir after idling will bubble and the temperature goes up into the middle of the gauge. if have never actually steamed out, but does bubble. we have replaced the thermostat, the radiator is find, oil changes up to date, etc,etc. someone i know had the same issue with his Chrysler and was told the "bleeder valve" had to be replaced and now the car is fine. help!

Answer
I need a little more info.engine size,miles,coolant age.One thing though,operating temp is straight up in the middle.when ever you work on the cooling system you will need to bleed it.There is a tool called a block tester you can use to see if you are getting exhaust gases in the cooling system,i e  leaking head gasket.I hope this helps.