So, I have been trying to diagnose a rattling sound on my 2012 expedition limited 2wd that only happens on acceleration. This sound is not present at idle, when in park and I hit the gas, nor when I brake torque it. At first I thought it was bad gas from sams club. So I filled up from a half a tank with chevron gas and put a bottle of techron in the tank. The sound is still just as prevalent. I have looked for any loose heat shields and have found none. I then thought maybe its pinging due to a vacuum leak. I can find no vacuum leak. I am at a loss as to what it could be. Any help would be greatly appreciated. Also, about 5500 miles ago I replaced the timing chains, tensioners, cam phasers, chaing guides and vct solenoids by following fordtechmakulocos 4 part video series on it. I have had no problems until the past 2 weeks and have even taken it on a 2000 mile road trip after the timing components were replaced. Below is a link to a video I took to help you know what I am hearing.