Mazda Repair: 1995 Mazda Millenia Overheating Problem, 1995 mazda millenia, mazda millenia

Question
After driving 5-6 miles, my 1995 Mazda Millenia temperature
gauge rapidly starts moving to hot.  For the first 5-6 miles the
temperature gauge is mid-way between cold and hot.  I have
replaced two of the heat sensors and the fan appears to be working
OK.  I have checked the engine oil and it does not appear to be
cloudy.  There are no apparent water leaks.  Does this sound like a
thermostat problem? If so, where can I get directions on replacing
the thermostat? What is the best way to diagnose the problem
without spending a lot of money?

Answer
Hi Wayne thanks for asking,
This could be a possible thermostat proble, since a brand new thermostat is cheap anyhow it will not hurt to put one in, if this does not solve your problem, have someone pressure test the cooling system, if this vehicle has a pressurized over flow tank a very minute air leak at the top of the canister can cause this kind of over heating, if all else fails the flow of the water pupm will be the next thing that has to be checked.
good luck
Chris P