Cant find raqdiator cap on my 2011 equinox; I see an expansion tank cap; I am getting no heat from heater

all cars do that when , the engine coolant is low
the heater core is full of AF coolant
if it makes noise , its got air there. (bad)
so with car dead cold.

take off the radiator cap, oops the coolant is low.
do the service on the car and this will not happen.
do not trust the side expansion tank, and for sure never let it run dry of this will happen.

run the car with the radiator cap off or the expansion tank cap off, which is part of coolant system and is pressurized, not to be confused with an overflow bottle which is not pressurized, and the heater on high. drain some coolant to allow for expansion. look/listen for bubbles. air from the vents should get hot. give it about 20 minutes

sounds like electric door motor is bad in front of the heater core. door is'nt opening

FILL COOLANT SYSTEM UP BY POURING COOLANT IN THE EXPANSION TANK UNTIL COOLANT LEVEL STOP DROPPING IN THE EXPANSION.WHEN YOU POUR COOLANT IN EXPANSION TANK AIR BLEED OFF THROUGH THE SMALL COOLANT LINES GOING TO EXPANSION TANK.WITH PRESSURE CAP OFF RADIATOR COOLANT LEVEL IN EXPANSION IS AT FULL COLD MARK.WHAT YOU TO DO CRANK ENGINE UP LET IDLE WARM UP UNTIL COOLANT DROPS IN EXPANSION TANK KEEP ADDING COOLANT UNTIL STOP DROPPING STAY AT FULL COLD MARK.WHEN COOLANT LEVEL START RISING IN EXPANSION TANK.PUT PRESSURE CAP BACK ON RADIATOR.WHILE ENGINE IDLING WATCH TEMPERATURE GAUGE.IF START CLIMBING TURN OFF ENGINE LET IT SIT FOR LITTLE WHILE TAKE A LARGE RAG OPEN RADIATOR PRESSURE CAP A LITTLE AT A TIME TO KEEP FROM GETTING SCALDING TO RELEASE AIR IN COOLANT SYSTEM.WHEN PRESSURE IS RELEASED OPEN PRESSURE CAP ADD MORE COOLANT IN THE EXPANSION TANK.CRANK ENGINE AGAIN LET IDLE WHEN TEMPERATURE GAUGE START CLIMBING. TURN OFF ENGINE WAIT FOR WHILE BEFORE OPEN RADIATOR PRESSURE CAP.WHEN YOUR THERMOSTAT OPENS WHEN TOP RADIATOR HOSE IS HOT AND ENGINE COOLANT TEMPERATURE GAUGE STOP CLIMBING AND COOLANT LEVEL STOP DROPPING IN THE EXPANSION TANK.ALL AIR IS EXPELLED FROM COOLANT SYSTEM TO KEEP ENGINE FROM OVERHEATING.

You still have a lot of air in the cooling system and you have to speed up the water pump to get any coolant to flow through the heater. Let the engine cool off, then open the radiator cap and top off the radiator. Pour the coolant in at a rate slow enough to let the air bubble up without splashing the coolant back out. Once you get the coolant level up to the top overflow hose, the remaining air will be pushed out by expansion through the overflow tank once the engine gets hot, and will be replaced by coolant from the tank on cool-down.

Only two thing could cause this problem. The actual radiator cap needs to be replaced or the neck is not smooth. If the cap is lifting prematurely it allows water to flow into the expansion tank. The second problem would be a leaky head gasket. This could be determined if the expansion tank has a black reside inside the tank. Changing the water pump and heater core was an expensive route the didn't need to happen.

Sounds like an airlock in the radiator,which will require the system to be bled out. The old school way was to undo the rad cap to relieve pressure,put the heater on full,slacken the bottom rad hose so that it leaks and then stick a hose into the expansion tank. Turn the hose on slowly until a steady stream with no bubbles comes out of the bottom hose. Now nip the bottom hose up,and turn off the tap. The only problem with this method is that it will flush out a lot of your antifreeze so it may be best to get a garage to do it for you. You could also have a faulty expansion tank cap. These need to be air tight to raise the pressure and allow heat to be generated a bit like a kettle. Could just be a few pounds. I'd try the expansion tank cap loose first with nothing else, leave the car like this,running for an hour,with the heater on max. You may get lucky. There is a slim possibility your rad fan could be gone too, listen out for it kicking in.

attach a hose to the topmost heater pipe and remove the rad cap/expansion tank cap.turn on the water .........flushed,use a funnel to add antifreeze into the top hose then connect up and job done..(please send the $140 to the charity of your choice,or buy a few beers).

If car heats up quickly and overheats , the problem is the thermostat. The thermostat stays closed and traps coolant in the engine untill it reaches about 185 degrees , than the thermostat opens and allows coolant to flow to the radiator where it is cooled by airflow. ( airflow while driving is usually sufficient ) while idling , or in slow trafic , the fan keeps air moving through the rad. The heater core is strictly for heat in the winter inside the car. The thermostat is the most likely cause of the problem , and even if it was good before , the overheat / boil situation likely cooked it anyways. I am assuming the water pump is still getting turned by a belt. No water circulation by pump would cause same symptom as bad thermostat. Overflow and expansion bottles are designed several different ways on different cars , but the theory is that as the engine heats up and the coolant expands , it goes to the tank. Later , as engine cools down after being shut off , coolant contracts. Radiator is replenished by coolant returning from expansion bottle.

The water (coolant) in the expansion tank will rise and fall with the engine temperature. What the expansion tank does is collect and return coolant to and from the engine. When the engine warms up the coolant gets hot, builds up pressure and opens up the radiator cap. The coolant then goes into the expansion tank. Now when the engine cools down the pressure drops in the cooling system and the pressure drop (vacuum) pulls the coolant back into the engine via the radiator cap. The radiator cap allows the cooling system to build up pressure and by doing so increases the boiling point of the coolant, but when that pressure exceeds the caps rating the cap opens and the coolant goes to the expansion valve. The cap has another part to it that when the engine cools down and a partial vacuum is created in the cooling system a "valve" in the radiator cap opens and allows the coolant to be drawn back into the engine. I would look at your radiator cap to see if any gunk or build up is on it, and check the rubber gaskets for cracks. It's easiest just to replace the cap because they are inexpensive and easy to replace (2-10 dollars). The expansion tank should have two hoses on it. The one on the bottom comes from the radiator and the one on the top (possibly part of filler cap) runs down and is open to the ground. That way if it is overfilled or becomes overfilled it will slowly leak onto the ground. When and if you change your radiator cap, make sure the engine is cooled down, remove cap and start engine and turn heater to full blast, full heat. Leave the cap off and let it run until engine warmed up. This should burp out any air pockets that may have happened when coolant was changed. Also top off the coolant in the radiator while it is running. Hope this helps and good luck