Had problem with temp gauge not working with engine light on. Switch out old stat and replace with new, the stat that came out was sealed close with heavy duty sealer,is that freaking normal?

 

no. that is not normal.. Sounds like someone added some stop-leak ?

 

Or, the original gasket that seals the movable valve was badly
Malformed Like mine was when it was removed. If bad enough it could be mistaken for a black sealant rather than a black gasket. If it was a stop leak substance, I would have expected the thermostat would be in a sealed position, rather than jammed open which would typically be indicated by the temp digital display showing "----" and accompanied with the CEL.

But then again I maybe wrong. :)

 

aaaah, the OP said it was sealed closed

 

So noted. That seemed kinda odd, as the engine would have been overheating, and the gauge, I would have expected, would have been off the chart.

When the thermostat is removed, it is cooled, and therefore in the closed position - and I thought the old malformed gasket might have been mistaken for something else.

 

Yeah, might be old rubber gasket,just that it looked like a dam good squeeze seal job. Simple repair. I mean getting to the part rather easy.

 

Agreed, & point taken...