I have a 97 Grand Prox GT with 167K on the Odometer. I had replaced the radiator about 2 years ago and a coolant elbow about 6 months ago. I have a 180 degree thermostat. I have this because I have used DHP Programmed ECM and it was programmed for that thermostat. I run premium gas because of the ECM. I believe the fans turn on at an earlier temp hence the need for the lower temp thermostat.
As of lately I have been seeing the temperature get pretty high. I would normally get to about 185 and it would stay there for the entire trip. Now a 15 minute trip to the fast food joint caused it to end up at about 195. It is about 85 degrees and really humid since it is start of summer.
My AC does not work as good as it should for some reason. I replaced the compressor with a used one so I think it just is going out too. It doesn't leak Freon because its always the same temp and it wont take anymore Freon but it wont get really cold.
The other day it got up near 200 so I turned of the AC and shortly it was down to 185 again. I am reading this with my Bluetooth OBD II And Torque Android App.
Before when I found this issue I would add some water to the overflow tank since I would see it was dry and some air got in or was low on coolant. I live in Texas so I run 30 percent coolant in my water mix. I use dexcool replacement and I just bought some water wetter type coolant and added 4 oz per gallon as per the directions.
The reason I went ahead and replaced the water in the radiator because I wanted to add that stuff to the mix to get a cooler temp. But that doesn't to seem to of helped and is about the same.
Now is this normal to get this high of a temp with a 180 thermostat? I check the coolant level and it is good and when it cools down the I take off the cap it is at the neck so its not going anywhere.
The car doesn't seem to run any different but I am really used to things being really within spec when cooling systems are working right. But I have to think if the ambient temp is high outside that it would make the car temp higher regardless of the cooling efficiently.
Let me know your thoughts