Temp change wide range and little to no heat
I have read through the FAQs and tried a couple of the suggestions. My temp rolls up just past the 210 mark and rappidly dropps to 160 range. Then it creeps back up and so forth and so on. It seems like that is when the t-stat is opening and closing, but that seems like an awful wide range to me, am I wrong?
Secondly, I have little to no heat from the heater. I felt the feed and return lines going into the dash to the heater core, warm, but not hot (can easily hold on to them) and they feel approx the same temp as the upper radiator hose from the pump to the radiator.
A couple of notes: Just changed out the radiator, smooth, no problems. Worked out from what i could see all of the air. refilled with approx 70% coolant 30%water. Twice since i have done this, coolant has overflowed out of the overflow tank and then returned to the close to the proper fill level. There has been no signs of overheating on the gauge, I watch it like a hawk since i chaged the radiator. Every now and then I will get a loud squeel sound that is a constant, the next day the sound is gone and might not hear it for a week or two.
Is the water pump going out?
bad temp sensor?
bad heater core?
is there air trapped in the system?
Thanks for the help and let me know if you have any questions.