Coolant reservoir
 

Ok, this might sound like a goofy question but here goes. The last week or so I have noticed the temp gauge on the engine go up to between 3/4 and just below the H on the gauge. I checked the reservoir and it was empty. I added some coolant, started driving and the gauge again rose to just below H. I cannot for the life of me see any puddles under the car, all hoses look sound, and nothing out of the ordinary is occurring. Is it normal for the reservoir to be empty? I know it's just an overflow. When I pull the radiator cap off, it is always full with coolant. Am I searching the wrong symptom here and maybe I have a bad thermostat causing the gauge to raise.

I would appreciate it if someone could give me some clues.

Oh yeh, 98 Sebring Coupe 2.5L.

If you are losing coolant with no visible leaks, that could be a sign of a blown head gasket. Do you see a puff of white smoke on startup? That's another sign. You can confirm a head gasket problem by a compression test. Let's hope it's not that.

The coolant should fluctuate between the warm and cool lines on the bottle, not run dry.

You might want to have the cooling system pressure tested (a totally different test than the compression test mentioned earlier.) and go from there.

I hope that's not the case, it only has 117000 miles on it.

I had the car looked at by my mechanic and he found a leak in the upper radiator hose. All seemed to be well but then today we were on the highway with the ac on and the temp gauge topped out again. I got home and the resevoir was full and spilling over. After it cooled down the resevoir emptied. What can this mean?

I think you need to run that compression test.

Ended up just being the thermostat. Thanks for the help.