I have a 1992 Volvo 240 wagon with about 470,000 on it. The engine coolant sensor does not work reliably. It seems like it will take a lot of work and potentially be expensive to resolve that.
So, I would like to use one of those infrared temp sensors that you can point at something and read the surface temp. I have been advised that the most accurate readings will be taken on the outside of the housing where the thermostat is installed.
What kind of temperature values should I be looking for once the engine is fully warmed up? What is the threshold that I do not want to exceed?
Thanks for any advice with this.