Strange Ticking Noise in Engine Bay

Installed the AMS CPS system and while I was attempting to bleed air from the coolant system, this periodic ticking noise started at idle. It would go away whenever I revved the engine. I heard it from inside the cabin with the hood popped. I was initially scared that it might be pinging (even more so after a conversation with a friend here), but then spoke to another friend who works at Bosch and he thinks it too periodic to be pinging, it’s also happening at idle rather than with load.

FWIW I haven’t driven the car much in the past month and the gas has probably been in there for that entire period. Any guesses as to what’s going on? Just DI pump noise, which is strange since it goes away? My guess is something to do with the SC loop pump?

https://www.youtube.com/watch?v=l5MALuDQSqQ

Thanks guys. I can make a better video to show the transition between the noise going on and off.