This seems to be a direct consequence of the water logging issue I had posted a few weeks ago. (water had gotten into my car after all the drain holes were plugged with dirt, leaves etc.) All the drain holes are and there is no trace of any water at the moment.
Anyhow, the engine temp. ticks over toward the right end of the scale everytime the car is idle for more than a few minutes or if I'm moving at very slow speeds. At speeds of 50 or above, the temperature scale slowly moves back to the middle (but not enough to say it's normal). My first thought was to check the cooling fans and coolant. However, there is no coolant leakage, oil pressure is a normal 40-60psi and cooling fans seem to be working fine. Someone on another forum mentioned about a cooling system flush? How easy/difficult is it to do that? Are there any other solutions or recommendations?
Thanks.. reps to all useful answers.