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Discussion Starter · #1 ·
I changed the thermostat on my 08 3.7 canyon since it wasn’t displaying the temperate at all on the cluster, the needle would not move and stay on cold. The ac off thing also displayed on the dash. I put the new one on there and then went to burp the system. The first thing is that the p0128 code was still displayed on there even after the change, another is that it doesn’t feel like that the coolant is circulating through the hoses at all. I poured the new coolant into the reservoir and it never went down in level even after the truck running for a few minutes. I didn’t feel any coolant in either of the upper radiator hoses. The temperature needle in the truck got all the way up to 3/4 and never went past it as well. Some additional stuff to note is that the ac off went away after changing it, the needle started working, and I can’t tell if the ac actually works because my ac/heat fans don’t turn on.

What should I do to get it to flow?
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It won't flow if the thermostat isn't open.
Did you install the thermostat correctly?
Perhaps the thermostat is opening and the pump isn't working, take the belt off and see if the pump turns.
From your description, I would say you have a bad temp sensor.

If the reason coolant won't move is an air bubble, try parking uphill, remove the cap and hope the air moves.
 

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Discussion Starter · #3 ·
It won't flow if the thermostat isn't open.
Did you install the thermostat correctly?
Perhaps the thermostat is opening and the pump isn't working, take the belt off and see if the pump turns.
From your description, I would say you have a bad temp sensor.

If the reason coolant won't move is an air bubble, try parking uphill, remove the cap and hope the air moves.
I sure hope I put it on right. I did have a little trouble putting the top bolt back on, but visually it seems okay.
If the pump turns does that mean it’s all good? I will say that I did not check the hoses to see if coolant was flowing through before I changed it so I can’t say if this is a new thing or has been going on.
I figured I should change the temp sensor too since it’s not hard to do.
Hills are hard to find here in Hampstead, you think if I just drive it up on my ramps that’ll be good enough? And I know I hear people saying to put the heat on full blast while you burp the system, is there anyway to do that with the fans not working & any idea on what to replace to get the fans working again?
 

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In the old days, the heater temp relied on a valve that controlled flow into the heater core; today the temp is adjusted with air flow, the core is usually free flowing.
I guess ramps are better than nothing.
 

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Discussion Starter · #5 ·
In the old days, the heater temp relied on a valve that controlled flow into the heater core; today the temp is adjusted with air flow, the core is usually free flowing.
I guess ramps are better than nothing.
I replaced the temperature sensor as well after getting those crows feet and noticed a small amount of coolant was leaking at the thermostat. One of the bolts wasn’t torqued down all the way so I tightened it and it solved that problem. I have it up on the ramps burping the system and it seems like it’s doing better (?). The other day it would still slowly get up to where it was overheating, but now it stops just a notch above halfway. I’ve only owned the truck for 6 weeks, but on my Silverado the temp needle was always a notch below halfway. Is it different for the small trucks or should it still be a notch above, or does the new thermostat open at a different temperature?
I also have not checked to see if the water pump turns at the moment, but it doesn’t feel like enough coolant is flowing through the hoses.
 

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Anywhere near that mid point is good, some may run a little below, some a little above, some right on the mid point.
If you take it for a drive and the needle stays away from the red your fine, no red, no air.
 
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