When I'm driving, my temperature tends to vary alot. It would be at the "a" on the temperature gauge and then in a matter of two seconds it will rise a little past the middle mark and then it will drop all the way back to the "a". Is this normal or what is the problem.?

 

when it goes half way up, then your thermastat opens and it cools back down
its normal to have temp variations, if it was over heating that would be different
i would get an auto meter machanical water temp gauge and oil guage
those stock gauges arent that accurate anyway