When I say move, it would push fluid out, then stop and drop in a fluctuating pattern.

I was told that these are a real pain to get the air out of the system since the heater core set pretty high. The guy said to pull the top hose off of the radiator and slowing add wateer to fill the core. I did that and as I put water in the hose, it would come out of the outlet where the hose attaches to the radiator. I then closed the system back up and started the van. It ran fine for ahile settling at the midpoint, then all of the sudden start shooting up. It was shut down for about 5 minutes and I went to move it back in the garage for the night and the gauge was back at the midpoint. Decided to take it for a quick trip and all was good until the guage shot up again. In about 10 minutes, it went from in the red to the midpoint and back to the red.

I am baffled...

 

As a couple of members had stated, the blades on the may not turnning to give you any flow. You can try taking the t-stat back out and leave it out and see how hot the engine gets.

 

I will do that in the morning and report back. Also getting a pressure tester to rule out head gasket tomorrow evening.

 

Well, pulled the t-stat and ran it without it and mostly water in the system. It ran for about 20+ minutes, most at the midpoint on the guage and then started climbing. It was not the same "flip a switch and rapid climb", but more of a gradual climb.

As much as I do not want to admit it, I think we are hitting the water pump...

 

Thanks for the help guys! I changed the water pump and all is good! No drips, no leaks, no heat.

 

Good job. Makes you feel good, doesn't it........

 

I have the same problem on my 04 3.3 caravan.