The analog water gauge in my 98 Mystique is sometimes temperamental! It suddenly move to hot then setltles...?

I understand that there is also another drain plug that I can screw out somewhere hidden on the back of the engine block usually at the bottom next to the torque converter housing. Right? This should take care of the vaccum glob! Funny the water pump cannot flush the vaccum glob out ??at high speeds, duh? I even left the water tank cap off for a short while while driving in hope of easing the vaccum glob out. No luck so far. I am trying to imagine the inner water chambers inside the block and cannot figure how the vaccum glob stay stuck there. Possibly it is plugged but it doesnt explain the temperental characteristic of the analog water gauge at like 15 minutes intervals or so. But it is fine while driving at high speeds for long stretches. Guess I need a lawyer to fix it..

The situation started last year when I drove up a steep winding mountain road for miles that I had to stop at every half mile or so until I cheated it over the top. Anyway , there was never any loss of antifreeze .Today I drove around for 100 miles until I got back to my hometown and it acted up. bizarreE!

I dont see any puddle under my car at all or any piss down the road whatsover..

I dont think there is any leak at all.. It looks like a block but where!! Maybe one of the radiator fans is flickering . There is one low speed fan and another high speed fan mounted on the back of radiator. I think the low speed fan is fried.