Originally Posted by HammerStriker
When they told me that it was definitely overheating, I brought this up as well. Which is what made them change the temp sensor even though it was testing ok.
I don't think they are taking a true temp reading, and just going off of the car's warning system, but I don't know that for sure. The whole thing seems really weird.
A bad head gasket can blow combustion pressure into the cooling system and cause intermittent overheating. This seems unlikely on a new engine and would be a worst case scenario.
Also, I not familiar enough with this engine design to know exactly what the symptoms would be on a failing head gasket. I have had the symptoms you described with a bad head gasket on V-6 engines.