Hi everyone, here we go again..

My FG2 with about 95k miles on it has developed a nasty ticking noise, I haven't been able to locate where it's coming from, even with a stethoscope. Additionally, at idle AFTER being warmed up, I start hearing a deeper knocking sound, it's very quiet, however on throttle tip-in from idle there is a brief loud rattle. I've attached two videos highlighting both noises (car is at operating temp in both). I don't hear any knocking under load when moving. Both noises are audible whether clutch is in or out, and vary with RPM.

The car runs fine when on throttle from what I can tell, without any hesitation, however at idle I can feel it misfiring, with frequent stumbles and small exhaust pops. Powertrain is completely stock, spark plugs are properly gapped and brand new, no leaking coolant or burning oil, and air filter is clean. This car is pretty "new to me" and I'm really stuck. Any advice would be greatly appreciated.

EDIT: The reason for taking the video's inside the car: The valvetrain and cooling fans are loud and made it hard to capture the noise in question on a crappy phone microphone.

VIDEO LINKS:

 

Have you replaced the timing chain tensioner?

Also, have you used the mechanics stethoscope on the idler and tensioner pulleys?

If the bearings are going bad in those, they can start making funny sounds.

And lastly, are you stock motor mounts? I believe the one side is a fluid filled mount and not sure how it would sound if blown. I have solid mounts so have not experienced the bad mount but know it's common.

 

Pull the serpentine belt and spin all of the pulleys and see if one either has roughness or is much different than the others.

 

I checked what I could reach at the time. The idler pulley sounds pretty scratchy, but no wobble or ticking. PCV valve is quiet and I have confirmed it is operating properly. The tensioner spring...I don't know. Timing chain tensioner is original (as far as I know), would I be able to tell if it's shot based on the spring tension with engine off? I'll be pulling the cover this weekend to adjust valve lash...I will try and check the other items you mentioned if I don't run into any surprises and the adjustment takes longer than expected. I've done my research, but it's my first time in there and I want to take it slow and steady.

Thanks for the help, I'll update you saturday or sunday.

 

I'll try this if time allows on saturday after valve lash adjustment. The noise itself doesn't bother me too much, I just want to verify it isn't anything too sinister causing it (ie rod bearing)...that would financially ruin me haha, I bought this car on the advice of mechanic family members because they told me it was as bulletproof as a sporty car could get.