My temperature gauge fluxuates from cold to hot,but my heater blows cool air then hot air...I don't know what to do. Also my hose the leads from the radiator collapses then gains its shape then does it again.

Is the coolant level full ? Are the heater hoses hot to the touch ? Do you know where the heater hoses are ? Out in the engine compartment going through the fire wall into the passenger compartment . 2 hoses , one carries hot coolant into the heater core the other is a return back to the cooling system . If hoses are hot you have a temp. door not working . When warmed up what does temp gauge show ?
Temperature Control
The temperature control operates in the following manner:

• Temperature control of the manual A/C-heater system is determined by the position of the temperature control knob (between COOL and WARM).
• This control knob is connected to a potentiometer mounted in the integrated control panel. This potentiometer is electrically connected to the A/C electronic blend door actuator that operates the A/C air temperature control door.
• The A/C electronic blend door actuator contains a reversible electric motor, another potentiometer and a printed circuit board. The wiper of the potentiometer is connected to the actuator output shaft and moves with the output shaft to indicate the position of the A/C air temperature control door.
• Battery voltage is applied to the ends of each potentiometer. The voltage available at each wiper indicates the position of the potentiometer. The printed circuit board drives the actuator in whichever direction is necessary to make the actuator wiper voltage agree with the control wiper voltage.

System uses a reheat method to provide conditioned air to passenger compartment.

• All airflow from the blower motor (18527) passes through the A/C evaporator housing where it can be cooled and dehumidified.
• Temperature is then regulated by reheating a portion of the cooled dry air and blending it with the remaining cool air to the desired temperature.
• Temperature blending is varied by the A/C air temperature control door which regulates the amount of cooled air that flows through and around the heater core (18476), where it is mixed and distributed.

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there are two hoses running to the heater radiator from the engine cooling system , one has a inline tap that controls the flow of hot water to the heater , check the tap is open , may be the control cable is not opening the tap , or it frozen and must be replaced.

With the vehicle cold, check your coolant level and fill it up it it is low. Start with your heater hoses. Check to see if one hose is hotter than the other. If so, then you have a bad or malfunctioning heater control valve (if equipped) or a bad heater core. If the vehicle never gets up to operating temperature, your should change your thermostat.

The dash gauges are notoriously inaccurate. But it is possible that the thermostat is stuck open. Does the upper radiator hose get hot after engine warmed up? Also feel both heater hoses-when engine is warm, both should be hot-indicating the coolant is circulating through the heater core. If heater hoses are hot, and you still have cold air, the temperature blend door on the heater case may not be operating.
Try a new thermostat and see if engine warms up faster and better.

There should be a vac controlled valve on the heater hose near the firewall. If that valve fails, or something happens to the vac source, the valve will not open or close. I would check that valve and make sure it is working. Both heater hoses should be hot when the engine is warmed up.

Check if the engine temperature gauge indicates a normal reading. If it's normal, your heater core may be blocked, or the temperature control mechanism controlling the flap allowing the hot air is not working. If you can open up the hood and find the two hoses leading to the passenger compartment, see if they're both hot to the touch. If they are, then the doors are not moving properly diverting the air through the heater core. If it's cold then the core is probably blocked and may need replacement.

Sounds like there may be an air pocket in the system.
Try 'burping' the system. If this still doesn't fix the problem, check the temperature of the heater core hoses (in and out) The inlet should be fairly cool, the other should be piping hot. If they're both cold; the heater core has an internal blockage.

Next, replace the thermostat with a winter (180-195 F) derivative.
Bleed the system accordingly, and keep me posted!

A thermostat stuck in the open position can cause both of these problems

Hi
I would first check to see if both heater hoses are hot to the heater.
if 1 is hot and 1 is cold the heater control valve is closed or the heater core is plugged.