So about 10 months ago I changed my clutch flywheel and counter balance. All went well and I was driving my car for a few weeks and started hearing this noise.

Now when I put in the counterbalance bolts one of the bolts I thought I may have been over tightened.
So when I started getting the noise I thought the bolt on the flywheel counterbalance that I thought overtightened was backing out and was rubbing on the clutch disk. Cuz that’s what it sounded like. So I parked my 8 and waited until I had the time to take off the transmission to get to it. So this Christmas break came up and I had the time. So I braved all the spider webs took off my transmission and to my dismay the bolt was good and tight and didn’t back out at all. So the car runs fine I haven’t felt a loss in power it starts up fine. When my batt is not dead. Just wanted to know if anybody had any ideas. I checked my spark plugs because I saw a video that the spark plugs were not secured and that’s what the noise sounds like. Buuut they are good and tight.
Thanks guys.
Spark plug not secured sound.
My car

 

Here is a longer video

 

UPDATE!!
Ok guys.. i have figured out this noise..
it is the Starter.. The Starter gear is not fully retracting after it has been deployed and is being spun by the flywheel gears.. I jacked the car way up and crawled under the car and the noise is coming from the starter. I took it off and it is only half way retracted in the starter.. I also loosened the bolts when the car was running and the noise changed etc as the starter motor was moved. Im going to try to take it apart and hopefully clean the starter and see if I can get it to work properly... My car has sat for a year because of my stupid starter.,. ok ok.. and my laziness... lol... Now second problem..... P0037 (bank one sensor 2) changed secondary 02 sensor still pops up after i clear the code run the car. Turn off the car code pops right up.. My though is the wiring however, any thoughts on where the #2 o2 sensor wires may be problematic?

 

Good work finding that ... would not have guessed it was that from the video .

Re the sensor : could it actually be a fault with the cat perhaps ?

 

Checked The wiring it was crispy at the harness side connector under the wire loom and tape.. I fixed the connectors and wiring harness CEL gone. I did however open up the starter and found that the engagement fork for the starter gear had broken.. (plastic part that moves the gears to engage from the starter solenoid.) I removed the part dancing around in the mix up and greased up everything. re installed at 12 am and tried it still not fully disengaging but noise is little less.. probably greasing the gears helped. haha.. anyway. new starter ordered.. RX8 should be back at it soon..