Some not all airplanes have gauges for multiple things. You’re probably thinking of flight instruments. Almost all airplanes are all about redundancy. When your truck has a major mechanical problem you can typically just pull over... an airplane doesn’t have that luxury... You also check all of the fluids before flying (or should) and perform an engine run up to make sure everything is in the green (good). How many of us can not say we check the fluids, do a complete walk around inspection, and do a run up each and every time we jump into our trucks. Having the tools to diagnose/monitor your engine, doesn't make it fool proof. That being said here’s a picture I took a couple weeks back when I was flying. Each cylinder has its own EGT and CHT probes/sensors. Cylinder 2 had a high EGT and low CHT... the cause... that cylinder had a bad injector that was over fueling the cylinder. Didn't show on the run up.
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