So I've had my 04 TL since October, and I'm pretty sure it came with this sound. 210k on the clock. This sound only shows up intermittently. When it does show I only hear it really well when I'm next to a wall (like a drive thru line).

Link (turn on sound). It's the like ticking(?) sound in the background. A little hard to hear but it's the only way I could capture it.

That's my driver's wheel so it's not coming from the drive belt. Anyone ever heard this?

edit: I can only hear it while idling. As soon as I rev, I can't hear it anymore

 

I dont think it's a tapping, sounds more like a squeal...

I bet it's the tensioner, as it spins, you can hear it change frequency

 

Interesting, a squeal? Not how I would describe it. And are you referring to timing or drive belt tensioner

 

it's like a high pitched metallic sound. and you can hear the pitch go up and down (understandably why you chose a tapping descriptor). but it's actually something spinning very fast and has a wobble to it...hence the changing frequency or tapping.

take off the serpentine or drive belt and see if it still makes that noise

 

UPDATE 2 years later:

So the sound has never gone away. You kinda have to listen for it, it's subtle. It's that high pitch clicking sound from the original link up there.

Anyway, I just noticed that this sound goes away entirely with the clutch depressed. Clutch all the way in, NO sound. Goes away instantly. I let clutch out, no sound for a second then it starts up. All of this is in Neutral. Throwout bearings make noise with clutch ENGAGED, right? Anyone have a clue what this could mean?

 

By clutch engaged, I mean when clutch pedal depressed***

 

Try applying pressure to the clutch pedal, like once you hit some resistance hold it there (so the clutch isn't disengaged). Does the noise go away? If the noise goes away it's because when you slightly press the clutch the slave clyinder makes full contact with the fork so the noise goes away. When you have your foot off the clutch, the vibration from the transmission and fork constantly make contact with the metal ball from the slave cylinder; causing that metal on metal squeaking noise. I fixed it by cleaning the part of the fork where it makes contact with the slave cylinder and applying some moly grease there. Noise hasn't came back, but sometimes I put some more grease during oil changes.

 

Noise goes away as soon as I breathe towards the clutch. Even the slightest contact. I'm gonna give your idea a shot and let you know.

 

So did it work?