Engine temperature sensor

[monchochos]

I want to measure and display temperature of components inside a car engine bay. For example engine head temperature and intercooler temp. The sensors will be mounted onto the surface of the engine components. Normal surface temp should be around 90degrees C, but during a cooling system failure it may be upto around 125degrees C.

Which temperature sensor would you recommend for such an application. Will the digital sensors survive temperatures over 125degrees for short periods?

Also which of Adafruit's 128x64 graphic LCD modules will more readable in sunlight?

[adafruit_support_bill]

For sensing engine temperatures, I would go with thermocouples. https://www.adafruit.com/index.php?main ... ermocouple

If you check with suppliers such as Omega, they sell "washer" tipped versions designed to be bolted to the surface of machinery for temperature measurement.

LCDs in general do not do well in direct sun. I'd avoid the touch-sensor ones because the touch sensor overlay reduces the contrast a bit more. You might also consider OLED displays. They are much better in sunlight: https://www.adafruit.com/index.php?main ... rch&q=oled

[monchochos]

What do I need to calculate temperature from this type of thermocouple? Do I need the amplifier circuit? Are they hard to calibrate? Why would you use a thermocouple of an active component?

[adafruit_support_bill]

Thermocouple output is in the microvolt range, so an amplifier is a necessity. The library will convert the raw signal to degrees. Individual sensors will vary somewhat and for maximum accuracy you may want to calibrate each sensor for 0C (ice bath) and 100C (boiling water).