oil temperature gauge

[wkucardinal]

My engine temp gauge seems to fluctuate constantly in the 50% range between hot and cold. Sometimes it will get up toward hot, then 5 seconds later it will drop below mid range, then it will be in the middle. This doesn't necessarily correspond to the cars performance. Sometimes I see all of these behaviors while cruising at the same constant speed of 60 mph. It's not overheating. What's causing this? COuld it be low on antifreeze? (I haven't checked yet.)

I Just got the car not long ago, and my mechanic lost some antifreeze when inspecting the alternator. I topped the coolant off with prestone 50/50 premix. Could this be cuasing the problem? That stuff is supposed to mix with any color/any mix.

-B

EDIT: title is supposed to say engine temp gauge.

[wkucardinal]

corrected the problem. low antifreeze. the reservoir showed full but after looking into the radiator i needed to add quite a bit.