Nissan Repair: Nissan Sentra XE 2001, upper radiator hose, thermostat temperature

Question
Hello Von:

Can you tell me where is located the thermostat (temperature gauge) in the Sentra XE 2001?

I was driving today and i saw the temperature was going high, not to the "H" but was very unusual. I stopped let the engine cool, checked the coolant and the reserve both were ok. Also checked if was i was dropping coolant and i did not see any.
I started driving again and about 20 minutes later i realized that temperature went up to 3/4 instead of the 1/2 usually is. Having observed this i rule out the water pump, so i guess it might be the thermostat but don't know where is located.
Thanks

Answer
Roger,

Follow the upper radiator hose to the engine and you will find the thermostat neck and the thermostat is inside.  Also, replace the radiator cap.  Do not back flush the system with a hose just drain the engine and radiator a couple of times.  If you use a hose to backflush your car the pressure will aid in the demise of your heater core.  A car runs at around 15 psi and your hose from the house is something like 60 psi.  Once done refill the system with a 50 / 50 mix of antifreeze and demineralized water.