My thermostat went to zero and the screen said, "air off to protect engine" what does this mean???

All the classic symptoms of a cooling system full of air. I answered this question so many times, I turned it into a Fixya Tip. The problem is that the heater matrix is high in the vehicle dash and stays full of air unless coaxed out. Also, the heater control must be on full heat so coolant rushes through the matrix rather than trickling.

https://www.fixya.com/cars/r29872074-vehicle_cooling_system_no_heat

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Your thermostat is a part in the engine cooling system. I suppose you mean that when you operate your heater you get cold air only. This could mean the engine is not heating up (so change the thermostat) or that the air blend door is not functioning (so vacuum leak or bad check valve in the vacuum control circuit or bad blend door actuator).

Loosing power is probably the computer trying to protect the engine from damage. The actual problem could be low coolant or a problem with the water pump.

means the thermostat went bad from just water they need anti freeze to keep it from rusting and working properly also when you add water when its cold next time run the engine so it goes threw the block also squeeze the the upper radiator hose to get all the air out sounds like you have a air lock

P0128:
P0128 OBD-II Trouble Code
Technical DescriptionCoolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)

What does that mean?This means that the engine's PCM detected that the engine has not reached the required temperature level within a specified amount of time after starting the engine. The intent of the P0128 code is to indicate a faulty thermostat. Similar codes: P0125

In determining the engine did not reach a "normal" temperature, it takes into account the length of time the vehicle has been running, the intake air temperature (IAT) sensor reading, the engine coolant temperature (ECT) sensor reading, and the speed of the vehicle.

CausesA code P0128 may mean that one or more of the following has happened:

Low engine coolant level .
Leaking or stuck open thermostat .
Faulty cooling fan (running too much) .
Faulty coolant temperature (ECT) sensor.
Faulty intake air temperature (IAT) sensor .Here's a link on replacing your thermostat.

Repair coolant leak.
If you cannot locate the leak, run a pressure tester and try to locate the leak.

bad low coolant switch or still low on coolant.

Engine Cooling The cooling system components are the:

• engine coolant temperature sensor (ECT sensor) (12A648)
• radiator (8005)
• degas bottle (8A080)
• radiator draincock (8115)
• water pump (8501)
• water temperature indicator sender unit (10884)
• water thermostat (8575)
• dual speed fan motor assembly

The water pump circulates the coolant.
The water thermostat:

• controls the engine coolant temperature.
• allows quicker engine warm-up.

The degas bottle:

• provides a location for fill.
• contains coolant expansion and system pressurization.
• provides air separation during operation.
• replenishes the engine coolant to the system.

The fan motor (8C607):

• operates only when the ignition switch is in the RUN position.
• will not operate with the switch in the OFF position.

The engine coolant flows:

• from the lower radiator hose (8286) to the water pump.
• from the water pump to the engine block and the cylinder heads.

A closed water thermostat returns the engine coolant to the water pump; an open water thermostat allows the engine coolant to flow to the radiator.
Engine coolant provides freeze protection, boil protection, cooling efficiency and corrosion protection to the engine and cooling components. In order to obtain these protections, the engine coolant must be maintained at the correct concentration and fluid level in the degas bottle.
When adding engine coolant, use a 50/50 mixture of clean, drinkable water and engine coolant.
To maintain the integrity of the coolant and the cooling system:

check the make sure you have no air in your system if there is an air bubble trapped in behind the thermostat your thermostat wont open and your car will heat up and stay hot while letting a small amount of coolant through the bypass so it wont overheat

Technical Information: When the engine overheats (goes above 220 to 230 degrees), the ECM (Engine Contro Module) will disable the AC (won't let the compressor engage). This is a safety feature of the EMS (Engine Management System) to reduce potential damage to the engine from an overheat condition. Check your coolant level in the radiator & reseviore -- Low coolant level can produce the symptom you describe -- if low, top them off. Inspect your radiator hoses/cooling system for any signs of leakage (crusty deposits of dried coolant). Wherever you find this, that's where it's leaking. If you don't find any signs of leakage, replace the thermostat (& gasket if required (as a precaution) anyway. When the engine overheats, both cooling fans should come ON HIGH! If they aren't/don't, something's wrong and you need to find the cause. Every two to three years the cooling system should be flushed and inspected to ensure proper operation/condition and system protection. Overheating can seriously damage the engine. $$$$. An ounce of prevention is worth a pound of cure.

Any time your car overheats, you need to shut it down ASAP or you can melt the aluminum parts of the engine or crack a head gasket, a repair which is the automotive equivalent of open heart surgery.
The AC cuts out to protect the engine from heating even more. But what you can do to bring down the engine temperature is to switch on the heater, but even this is only advisable for a couple miles or so until you get to a repair station. At this point, your check engine light should have been on. Any time that light is on and you don't know the reason, you need to call roadside assistance if you are not within 5 or 10 minutes of a safe place to pull over.
If the thermostat sticks in the closed position, it means that no matter how much coolant is in the reservoir it is not able to circulate freely through your engine. The thermostat can also get stuck in the open position, meaning the car won't warm up when you turn the crank (car runs too cold).
According to some car care guides, the thermostat should be replaced every two years. It is a VERY cheap part, but if it fails and you continue driving the car in an overheated state, you might be looking at a new car and/or a new engine. Running your car overheated is not much better than running your car with no oil in it. Those are two surefire ways to fry the engine.