Okay. We need to measure resistance of the sensor and see what it is reading. This will tell us if the gauge is accurate.
If you don't know how to do that, you need a multi meter and back probe the sensor on each wire and put the meter on ohms. Then see what it says. It should read about 24 ohms if the PSI is 15.
As for your attachment, what they mean by the gauge reads low and stays low is it stays at 0 when you start the engine. Not a low reading like you have. If the gauge is 0 when the engine starts and remains there it is the gauge. Then that is misleading as well because when they say the gauge, that could mean the sensor as well.
If it were accurate it should say "if the gauge does not give a reading after the engine starts and warms up then the gauge is not giving an accurate reading and need to be diagnosed. When an engine is running, it has some amount of oil pressure so if the gauge says 0 then it is not accurate."
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Saturday, December 7th, 2019 AT 6:31 PM