While the car idles, the temperature gauge goes way up, to the point of indicating overheating although I have yet to see it overheat. As soon as I start driving, the gauge returns to the "middle/normal" range. Any ideas?

What is your question?

Yellow engine light was on for about 7-8 days about three weeks ago then turned off by itself, now temp gauge says it's overheating when I am stopped for more than 4-5 minutes.

What makes this problem better or worse?

Soon as I start driving, needle moves slowly back down to normal range.

How long has your 2004 Honda Pilot had this problem?

This just started less than a week ago.