I have a 1998 Chevy camaro. I just changed the fuel filter. It was a nice day. I keep looking at my oil gauge and it keeps flickering when it sits. When you drive it the oil pressure gauge doesn't flicker anymore. What could this be. I read it could be the oil pressure sending unit. Where is this at and how do you get to it. It is a 1998 Z28 Chevy Camaro 5.7L V8. Thanks.