Heater blows cold air then hot air then cold air. but mostly cold air

Check your coolant level. Especially after you drive it and it starts to cool down. You have air in the system and it needs to be purged. Sad to say but chrysler/ dodge are bad for this problem. Some times you have to remove the hose from the heater core spout to get it purge correctly. You have to do this while it is running.
Randy

Check the fluid level in radiator !st. if low then thats problem. if not that, you may have a thermostat going bad.does temp light or guage say it's running below temp. or maybe when it's too hot, then it blows cold air? if so, it's bad thermostat. hope this helps!!

Hello Vicaugus.
Your cooling system fluid level is low and air is entering the heater core hoses.
Allow the engine to cool and remove the rad cap.
Fill it up with the proper mixture of coolant and water for your area.
Check the cooling system for leaks after it is warmed up again.

Thank you for using FixYa.

KL