EDITED: So my temp gauge will drop to zero. Randomly and immediately. And the AC cuts off and fan kicks wide open. I’ve searched and searched and can’t find a resolution to this. I have replaced the coolant temperature sensor at the coolant/water outlet (circled in green) on the driver side of the engine and I cleaned the plug with electronics parts cleaner. Didn’t fix the issue. Now comes the confusing part. Apparently some Cruzes have 2 engine coolant temp sensors and a few early Gen 2 Cruzes only have 1. The second picture with the red circle shows the port for the second one which appears to just be a plug to keep coolant from leaking out. There is no wiring harness anywhere near it. No destroyed wires where it might’ve ripped out. Nothing. It’s like they just used a sensor to plug the radiator from leaking coolant. There’s also no sensor on the actual thermostat. I don’t think it’s the thermostat itself sticking open bc when it drops out and comes back in, the temp reading on gauge is immediate. Straight to zero and straight back to operating temp (when it DOES return, that is. Sometimes it’s out for a while.) If the thermostat was stuck open, I would assume a gradual decline in temperature, and likewise when it closed back up, a gradual rise in temperature again. If anybody has had experience with this and a possible solution, I’m all ears and would be extremely grateful!