Your oil pressure gauge indicates the pressure of oil moving through your engine. Oil pressure problems can be caused by worn bearings or a failing oil pump. These issues can cause rapid engine failure and expensive repairs. Oil pressure gauges are a necessity for performance vehicles which may see rapidly changing engine oil pressure as they accelerate. Though not all vehicles are equipped with an oil pressure gauge from the factory, those without one will usually have a warning light to alert you to oil pressure problems. If you only have a warning light, it is usually possible to add an aftermarket oil gauge if you choose. O'Reilly Auto Parts carries a variety of gauges that will fit any application.