So I have had this car for about 3 years now and just recently the heater has started to not blow hot air and when it does it’* very little and only blows through the defrost vents and the floor vents. I have looked for a cabin air filter but not sure if this year has one and have looked for the evap core and found it was very dirty so I removed and cleaned it to the best I could get it without damaging it, and still no hot air in the car or through the front facing vents. Is there something I’m missing??

Is the car warming up properly? If not, check the thermostat.

If I remember correctly, the climate control doesn't move the heater to the dash until warm air is coming out. Also, is the air that is coming out of the floor hot?

The car warms up as it should. And there is air coming from the floor but it’* no where near warm

Check the pipes to the heater core to make sure that they are both warm/hot when the car is warmed up. Both pipes should be a very similar temperature. If the heater core is plugged up, both lines won't be hot.

Also, check to just make sure that the system is full of coolant, and there are no massive air pockets stuck in there.

If the cooling system appears to be intact, then check the airmix actuator under the dash. I am not sure exactly where it is on that gen, but it tends to be under the dash, towards the passenger side. The newer generations have tons of issues with gears cracking internally, and jamming in one spot. You should see it swing from one side to the other as you command opposite temperature extremes.

Is the top rad hose firm when hot?
Re air or leak in cooling system, rad pressure test would be a good idea.
I do not believe that the 91 had a cabin air filter. Just below the windshield when hood open, ensure there are no leaves etc blocking the air intake.

Agree with Rjolly, touch the inlet and out heater core hoes.....BOTH should be hot....if outlet is cooler, either plugged core(backflush), or air pocket(coolant leak.....check reservoir AND radiator levels before starting cold car)........

If neither hose is really hot, and no coolant leak, possible thermostat....

If both are hot, then check temp actuator(a)....

If air flow was ok, there is no problem with the evaporator.....if there is an air flow problem, check for leaves in the squirrel cage, and if this does has a cabin filter, I believe it is located in the hvac module to the right of the gas pedal....you will see a removeable plastic cover....the filter comes out the driver'* side and is actually 3 pieces, interlocked, one on top of the other....