:I was told by a friend that some EGT probes use two different metals in the wire and the heat/resistance change across the two gives the gauge its reading? Is this the case> Specifically with the Defi gauges as well?
What your friend is talking about is a thermocouple. If you have two different metals in contact with eachother under high heat they will generate a small electrical charge. Measuring that charge is how you get the temp. I'd imagine thats the way all EGT probes read the temp.
