Temp gauge indicates overheating but no obvious signs
No leaks, coolant is at normal range,engine doesnt
feel noticeably hot, i can hear fluids moving around
at times like drainage when starting, and my gauge
will move up past halfway slightly below the red
zone and fluctuate a little while sitting in traffic
until i began to drive. The fans engage once it gets
up to that point. 2 different mechanics have
checked it and both diagnose no signs of
overheating. What could it be?