Ford heating issue

Had to guess, the stat is probably stuck open and won't close. On the sway bar are you talking about th busings or the bar itself?

-Doc

And what kind of a Ford would this be? If you just purchased the car, maybe someone left the thermostat out completely..Or, it could be frozen open, the wrong stat might have been installed in some cases, or it may have been improperly installed.

People dont normally replace sway bars, unless you are building up a racing suspension. You can replace the bushings easily enough.

Why is the coolant a week old? Preventive maint or some sort of repair? Did it do this before the coolant was changed? If no, then you need to "burp" it to get out the air that was introduced at the change. If yes, probably a bad thermostat or temperature sensor.

I'm guessing you just bought this thing and somebody told you it needs to be changed? A thicker bar can make it corner better. Replacing just the bushings can tighten things up and make some rattles go away.

Is the radiator full? All the air purged out? If so, sounds like a tstat...

Modern Fords purge themselves. But it's a good guess. Really not enough info from this guy, no year, model or for that mater which vintage heating system. I'm going to make a guess because I own a '95 Ford with Electronic Automatic Temprature Control. Called EATC by Ford and it is a computer controlled system. The EATC modual, in the dash, is bad. New from Ford it's over $500. Good part to get from a junk yard but you have to know a little bit about what you are doing.

Is this in something like an 01-04 taurus?

I got the impression from the OP that the temperature gauge never moves, and he assumes the problem is related to that. Could be, or could just be a bad temperature circuit.