hello i am new to this , i was wondering if anyone had came across this before, i have a 2002 xterra, here recently i have noticed the coolant temp gauge climb into the high pretty fast, sometimes when i put the defrost on it does not go down, but if i kick on the a/c, the temp starts to go down, just wondering if this could be a thermosat problem or someone had mentioned to me maybe the temp sender is going bad, any info would be great , thanks