Can the oil pressure gauge go bad and and not be the oil pump? If so, how can you tell that the oil pump it self is not going bad.
Oil pump/Oil pressure gauge on 2005 Chevrolet Silverado 1500
Usually a mechanic will install a mechanical gauge on the engine and test pressure before changing any parts
While in Park, turn the ignition switch on, but not far enough to start it. Observe the guage. If it jumps up, or maxes out, it is a sensor, or sending unit, and not your pump. It is safe to drive without worry, but keep an eye on your oil level. Hope this helps.