2018 Encore - What would cause my coolant system to not flow well enough (or at all)?

jegslegs

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This was an instant problem, not something that built from a small overheating issue like a fluid leak. The car was working fine and all of a sudden the temp. gauge jumped to high and I received a warning that the engine was overheating. I checked the fluid levels, they are fine, I just changed most of the plumbing and the reservoir so I know there isn't a clog in those...

After letting the engine cool completely, I will restart it and within a few minutes the temp. jumps all the way up. So, I'm assuming the engine is receiving no coolant at all. The only code I get is p00b7 - improper coolant flow. If it were the water pump, wouldn't I get a more specific code for that part? Should I start with the thermostat? It being stuck makes the most sense, in my opinion, because of how quickly things went from good to bad.

Thanks for any recommendations or advice.
 
This was an instant problem, not something that built from a small overheating issue like a fluid leak. The car was working fine and all of a sudden the temp. gauge jumped to high and I received a warning that the engine was overheating. I checked the fluid levels, they are fine, I just changed most of the plumbing and the reservoir so I know there isn't a clog in those...

After letting the engine cool completely, I will restart it and within a few minutes the temp. jumps all the way up. So, I'm assuming the engine is receiving no coolant at all. The only code I get is p00b7 - improper coolant flow. If it were the water pump, wouldn't I get a more specific code for that part? Should I start with the thermostat? It being stuck makes the most sense, in my opinion, because of how quickly things went from good to bad.

Thanks for any recommendations or advice.
Yes, remove the thermostat and test in a slowly heated pot of water to see if it opens
 
Yes, remove the thermostat and test in a slowly heated pot of water to see if it opens
Ok, it was indeed broken. Thanks for the response. However, I also discovered the belt to be shredded, so that was the problem too. I suspect the thermometer to be a lucky catch because no belt is much more of an issue. I'm making another post because the tensioner pulley seems misaligned and there is strange damage to it that I can't figure out how it could have happened. It seems like the pulley was sitting too high (towards the water pump pulley) and the spring would bow a lot when I pulled the tensioner wrench. The little metal strip on the inside of the spring was very bent, almost sticking out of the spring...

Thanks for your reply though.
 
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