Engine Coolant Temperature Max warning
About 2 weeks ago, I had the coolant temperature warning come on and when I looked at the temperature gauge it was sitting at 130. The warning went away and the gauge returned to the normal position at the 90 mark. When I checked the coolant level it was a little bit above the min marker so I filled it up.
Now, this morning the warning sounded again and my temperature guage was moving randomly between the 90 and 130 mark. I checked the coolant level and everything was fine. Is this an electronics problem - has anyone had a similar problem?
Also, is the coolant just water or a mix of water and something else?