What is this noise? Spark knock? —1994 SSEi

[Highway Patrol]

Can someone tell me what this noise is? My guess is spark knock since it only happens when the engine is under load (I put it into reverse to do this) and it will also do this when the oil cap is removed. Also: are spark knock, detonation, predetonation, preignition, and Low-Speed Pre-Ignition all the same thing or are they different? I can’t find any good examples of this sound anywhere and it’s getting me worried. I should add that I might have a Lower Intake Manifold leak (judging by the steam from the exhaust... but it’s completely odorless would it not be Coolant?). I’ve got other videos on my channel talking about this so you can go ahead and watch those too if you want.
Also, here’s a link to the video I took of the sound I’m hearing: https://youtu.be/jD40N7vRnH0

[95naSTA]

It sounds like metal touching. No idea what. Putting the engine in drive could move the engine enough to make it worse.

[Highway Patrol]

It sounds like metal touching. No idea what. Putting the engine in drive could move the engine enough to make it worse.

I did notice that my exhaust heat-shield bolts literally all snapped so it is resting on the muffler. That makes a different noise though. This noise sounds like it was coming directly from the engine (couldn't get the hood up because it was covered in ice). I think I do have a major vacuum leak, judging by the amount of suction I get on the oil cap/dipstick and how the engine pretty much almost dies when I try to remove either of them. The gas is pretty old (the car has been sitting since may of 2018, but I have been running the car around every week or so. I did put $25 worth of premium into the tank back at the end of December (I think?) by driving it down to the gas station, illegally of course. Whatever old gas was in there has probably fouled out previously mentioned-fresh gas so, it makes me wonder. The car hasn't been registered yet so I haven't been able to start driving it anywhere on a daily basis. Honestly, thank you for the reply! I really hope that it is just some metal touching somewhere in the engine bay like you said haha.

[Highway Patrol]

Now, I'm not sure if this is the same noise (it sure sounds like it), but this is the noise I hear when the engine threatens to die when I remove either the oil cap/dip stick: https://www.youtube.com/watch?v=q08AWhvu7qc&t=4s

[Highway Patrol]

Judging by the limited amount of replies, you guys don't know either... Anyways, here's a better clip of the noise:
https://www.youtube.com/watch?v=pabi7mM ... 0111573153

[95naSTA]

I'm not sure what the clicking is at the beginning but that metal noise being in the accessory side of the engine makes me wonder if it's a bad supercharger coupling. If you take the belt off and move the pulley back and fourth, there should be no play before you feel it moving the rotors.

Either way, if you run the engine without the belt for a very short period of time, you can limit it to the supercharger, A/C comp, waterpump or associated idler/tensioner pulleys.

[Highway Patrol]

I'm not sure what the clicking is at the beginning but that metal noise being in the accessory side of the engine makes me wonder if it's a bad supercharger coupling. If you take the belt off and move the pulley back and fourth, there should be no play before you feel it moving the rotors.

Either way, if you run the engine without the belt for a very short period of time, you can limit it to the supercharger, A/C comp, waterpump or associated idler/tensioner pulleys.

Huh, I never even gave the supercharger coupler any thought? I’m pretty sure the supercharger as a whole was replaced a few years ago for failing bearings. I’ll definitely have to check that out!