I have an 05, 3.4L Monte Carlo. I replaced the coolant sensor and I am wondering if it is possible to crack the hole it screws into if it was tightened to much because now I am leaking antifreeze underneath where the the sensor and thermostat is located. And if it is cracked, do that mean the engine is shot and would have to be replaced? And is there an easier way to get to the thermostat without having to remove the manifold?

 

Yes it's definitely possible to crack something if overnighted. At the top of my head I cannot recall if that had sealant on the threads on that or not. As for is the engine shot ? No is the answer. There's a few things you can try otherwise you will have to replace the lower intake manifold , problem solved. Try removing the sensor again and inspect hole with a inspection mirror for a crack . At this point I would return the sensor for a new one and either use pipe thread sealant or JB weld as you have nothing to loose but replacing the intake. Good luck