Oil. It’s quite important stuff in engines, especially in aeroplane engines. Considering the only thing keeping us up in the air is the engine it makes sense to keep a close eye on the oil.
He who is without oil, shall throw the first rodCompressions 8.7:1
I have an issue with a low oil pressure reading. It would be less irritating if there was some oil floating around in the cowling, or a stripe down the fuselage, but no. Not a drop.