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The early Miatas ('90 through '94) were built with genuine, working oil pressure gauges. It had real PSI markings and the needle actually indicated the oil pressure of your engine. In '94, Mazda replaced the gauge with an "idiot gauge" which looks like an oil pressure gauge, but in reality only has two possible needle positions - just like a light but less useful since it gives the false impression of showing a reading. The good news is that it can be replaced with an earlier gauge to give genuine oil pressure readouts.
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