My temperature gauge on my 05 Kia Optima is going into the red when the car is stopped or going slow.?

When the car is moving the temperature is fine (running at the medium level or below) but within a minute of me stopping at a red light or being caught in traffic the temperature gauge starts to move towards the red. Once I start moving again it starts to cool back down to a normal level. If I turn off the car and then start it up again in a few minutes it will start at a normal place but if I don't start going without stopping it does not cool down. Does anyone know if my car is actually heating up and cooling down a lot, or is it more likely that my gauge is broken.
My temperature gauge on my 05 Kia Optima is going into the red when the car is stopped or going slow.?
fan problem
My temperature gauge on my 05 Kia Optima is going into the red when the car is stopped or going slow.?
Classic sign of failing (or failed) radiator fan, fan relay, fuse, wire, etc.





When the car is stopped there's not enough air flowing through the radiator. So the fan is suppose to cool the radiator. But other wise even with a failed fan, the car would naturally cool fine.
Reply:These guys were all on track. I would imagine your problem gets even worse when you run your a/c? The problem is could be a couple things in the cooling circuit. The fan is least likely, although I like to check first. Perhaps a relay isnt contacting anymore to switch the fan on when needed. The last is either a crushed wire perhaps, or a sensor...a.k.a. the signal. Hopefully this makes sense, at least to be prepared when you go into the shop? I HOPE! Dont KIA's come with good warranties?
Reply:If the gauge is moving up and down, it probably is registering correctly. I'd check to see that the cooling fan is operating properly and that your coolant level is full. Also check to see if anything is obstructing the air flow into the radiator such as dirt dust leaves etc. A/C being on may or may not make a cooling fan problem worse. I'm not familiar with KIA's but sometimes A/C may force the cooling fan on and lowering the temperature depending on what the problem is.