Airplane. Cessna 152. I'm pretty sure it's a bad oil temp sender or gauge. As particular as they are about some things, the temp gauge is about as close to an idiot-light as you can get and about as unreliable too. It's basically just a volt-meter, if the voltage regulator is cranked up too much it'll indicate high oil temp. It was originally manufactured as a 12v instrument, to run on 24v they added a resistor to the back of the gauge - but if that resistor starts to break down it'll read high. Dumb!