Heater blows cold air. I have checked just about everything and am so frustrated.

My x husband disconnected the heater coil because it was leaking coolant into my car. He replaced the heater coil last year but I couldn't get hot air to come through. I have checked the fuses and both the hoses are hot. I have checked the blend door behind the glove compartment that opens and closes when you  change the vents you choose for the air to come out. It works fine and I am able to see the levers and motors when taking apart the lower part of the dashboard apart and they all seem to work fine. While I was under there the last time I wiggeled the wire harness that is attached to the heater coil at the top of the dashboard and squeezed the hoses and all the sudden the heater worked great. That lasted about 2 days. Sometimes it works when I squeeze on the hoses. Sometimes it will work if I turn my car off and start it again. Tonight it was working just fine and then just faded out and now wont come back on. Please help feeling hopeless!