no heat at idle only when driving i have replaced the thermostat

My 02 montero is having the exact problem of a faulty temp gauge. It seems to be quite a common issue. So I looked up this problem online and came across a solution very viable. Go to "pajero.guru" and just scroll down and you will find a step by step instruction on how to make the repair , as well as other notorious issues on monteros. I'm very thankful to this webpage, for helping us with our Montero misfortunes