I need you to let me know if the engine is reaching operating temp. at the gauge. then also when warm, do botht he heater hosed going into the heater core feel warm and close to the same amount of heat. Sounds like you may have a plugged heater core in which I will next ask you to try flushing out the heater core. you can remove the right side(passenger side) heater hose by the manifold and remove the left side heater hose by the water pump. flush core with garden hose and you should see a steady stream off water coming out the other end of the hose. Also reverse the direction of the flush. do this for 10 min and hook up the hoses and tell me what you have,
Thanks , Tony
I need to see if the heater temp cable is moving properly. You may have to remove the heater control head to gain visual on the cable and on the door. Picture below is what the cable will look like and what it is attached too.
The heater control head is wha you adjust when you turn the heater knob. I really want to know if you can just go under your dash and at the same time move the temp mode button and see if you can see the cable move. The cable should be towards the top of the heater box so it might be difficult to see, I just want to eliminate the possibility of a cable that is off the door latch or a door that is broken inside the heater control box.