http://forums.2gnt.com/dcboard.php?az=show_topic&forum=4&topic_id=43459&mesg_id=43459&page=

there is a thread discussing that issue right now. as for your overheating, check to make sure you have enough fluid in your cooling system. Also go by somewhere like Jiffy Lube and have them check to see if it's still protecting your system.

Do you have any kinda grill in front of your radiator? or anything blocking it?

edit* check your radiator cap as well, ive heard that if they lose pressure there your system wont be protected, also check your thermo if you can. I dont think its one of those cause you say it goes away when you drive off. Look a coupla threads down and theres info on overheating that FlyESi (?) posted.