Contour Enthusiasts Group Archives Forums Modifications Zetec Maintenance Should coolant temp stay fairly constant?

Even going into summer I would think the thermostat should maintain a fairly constant temp, granted conditions could make it vary a little but my temp runs with about a 1/3 deflection up the scale. Even at an oat of 75%f it will climb up to better than 1/2 occasionally 2/3's scales deflection especially after some hwy speeds then slowing down in town. Are these engines critical on the antifreeze water ratio?

You talk funny but I'll try to interpret. In heat, the ECT is gonna heat up until the low fan cuts on, and if it's not up to the job, then the high fan will bring the temp back down. If there is a problem or very agressive driving, then it's possible to overheat it.
Are you saying you are adding more antifreeze to try to get cooler temps? Bad idea. More water is what you want (still have to have enough antifreeze for system lubrication/protection and to not allow freezing).
You can add a lower temp thermostat that helps some but not much.
Also pick up a bottle of redline water wetter at autozone and put some of that in with the coolant.

You might want to take your own advise in your sig. j/k. Could possibly be your coolant temp sender is broken. Zetecs seem to like to do this, mine does too. Could possibly be getting odd readings because of that, not because the car is critical.

Check to make sure your radiator is clean on the outside in front of the fan. I know this is obvious but many people forget to check. Also check your condensor to see if the fins are bent where there airflows in through the bumper at the bottom.