ubreak_ubuy

i want to test if my oil presssure sensor is working. If i turn on the car and the oil pressure light on the cluster turns on and off after a few seconds, then that at least means it works... correct? because for some reason, my autometer electrical oil pressure gauge is not reading any pressure. i want to make sure i have some pressure since my motor has just been rebuilt. another thing, if i do have pressure, if i remove the oil filter, will oil come out? Im assuming it will be bone dry if there is no pressure. I will probably go pick up a mechanical oil pressure gauge and hook it up directly to the block and test but i want to do this first before i head down there. thanks everyone.