So I dropped both oil pans to fix a leak and did some other stuff like a front main seal. And while driving to work I had great oil pressure then it dropped down to nothing. Then 20sec later it came back to normal then about a mile or two down the road it dropped down to nothing and stayed there the rest of the 8 miles or so to work. So my question is how do I test to see if it's just the sensor or if I actually have no oil pressure? I'm at work so don't have many tools and just a volt meter. It seemed to run fine I didn't get any knocks yet. It's a 95 with a 4.5 liter