I have a 94 Accord LX with the f22b1 engine I have noticed recently that my Temp gauge fluctuates alot. I have changed the antifreeze and it still does the same thing. Could my problem be the thermostat? The car does not run hot but I am concerned. Also the cooling fan comes on after I shut the car off and runs for about 2 -3 minutes. Thanks in advance for the help.