I heard this light thumping/knocking sound by my inlets/exhaust side while doing a routine check for leaks. It appears that it’s not rpm dependent. In the video, I took it from idle to 1000rpm, 1500, and 2,000 and the tempo of the sound did not change. It only changed and went away after I shut the engine down. It’s light in volume and unless you’re really looking for problems, you wouldn’t normally hear it. I put my phone by the front inlet to be able to record the sound. Any ideas??