I just changed my oil today and i cranked it up to let it run for a minute so i could check for leaks. When i had the hood up I noticed a tapping sound that sounded like valves. i didn't notice the sound before and i've only had the car for a few weeks, so i didn't see how it could be the valves. But when i got home i popped the hood and i didn't hear the tapping sound anymore. So i started revving it up slowly and when it gets revved up it does it. My brother-in-law siad it might be the oil pump not pumping enough oil. I wanted to get some other opinions because i don't think it's the valves. I greatly appreciate any feedback. Also, i'm driving out of town this weekend so i need to know something

 

sometimes the oil weight will make a difference...

 

that makes sence, thanks