It could be the guides for the timing belt....nice job with videos, I'm at a loss as well, cam tensioners usually sound ALOT worse....I see you are mechanically inclined, so I'm assuming you've made sure none of your pulleys, water pump, ac wheel etc are loose or worn? Let me think on it today and play the video around some friends and see what a response I get here.

 

B2S1 is a primary (upstream) sensor, driver side.

 

I had the serpentine belt off and noise remained the same. That should indicate that water pump, AC, alternator etc are not the culprits? I only did a 'feeling and spinning test on those so far.

Priority for me is to rule out 'internal damage' (main bearings, connecting rods, pistons). If the feedback I get can rule that out with some certainty, I will do the time belt/water pump first. Then de-sludge (drop oil pan, new/improved pick up tube, oil as far as I know).

 

Interesting. A while ago, I had the B2S2 (driver side post cat sensor) error code:

16540 - Oxygen (Lambda) Sensor B2 S2: Malfunction in Circuit
P0156 - 95-00 - Unknown Error Elaboration

At that time also the:

17912 - Intake Air System: Leak Detected
P1504 - 92-00 - Unknown Error Elaboration
16785 - EGR System: Insufficient Flow
P0401 - 93-00 - Unknown Error Elaboration

Since then, I cleaned the clogged EGR passage (and EGR and TB), installed new injector O-rings (audible leak).

Didn't notice that now is B2 S1! Could be still vac leak and not faulty O2?

 

Is there are trick to get the passenger side timing belt cover off?
Both buckles are open, cover moves, but WON"T COME OUT!!
Been trying for 1/2 hour now.

 

There may be a third clip. Search carefully - nothing besides the clips holds it on.

 

I don't know where your noise is coming from but after watching your videos your timing belt is way too loose. I changed mine at 126,000 and found it was the original one. It had stress cracks on the flat side but wasn't near as loose as yours is.

Good Luck!

 

Can someone confirm if and where there is a 3rd clip?

 

Have O2 here now, will swap it out to see if code goes away (bad sensor) or if code is triggered by something else (vac leak?)

 

I'm glad to have found this thread.
Perhaps we can help each other, although my noise is brand new so you're ahead in the replacements and troubleshooting..

I too suspected a spun bearing, mostly due to the violence of the sound that came with it.
Clack - tac - tac - tac

Initially I suspected the 5spd trans, since it was run dry for a short period and I saw consumption climb for awhile afterwards, but clutch in and noise is still there.

Eventually stalled while tac - tac - tac sound went away, faded away, replaced with what sounded and felt like a misfire.
Difficult to restart, so feathering throttle and after several attempts away it went and uneventful rest of day. Sometimes just a dip in performance, like a miss.

So, while a spun bearing is still a possibility, I'm now thinking a hung/sludged or jammed lifter.

I've had lifter tick forever, although not bad, but my car sat for nearly a year, then this started happening intermittently, like a miss, stumble or similar that I couldn't attribute to weather or driving conditions. I suspected water in the fuel as well, since it did go away, but lasted for over a tank's worth.

BTW I have the same code for airbags.
No other codes on full scan.

I think seafoam is in my future, but I know a compression test is...