There's a really weird clonky sound at idle, not very steady either. It goes away after revving but then the engine starts ticking really loud and that's probably a separate issue. It's got 140k and the timing belt kit (Gates) was done about 2 years ago at 129k.

Any help would be greatly appreciated, thanks

 

I think you should remove the drive belt and start it. If it goes away then it's one of the bearings, if it doesn't then remove the timing covers and start it. It could be your timing belt tensioner failing. Your engine itself sounds okay, it sounds like a loose bolt rattling. Also pay attention to drive belt tensioner while it's running, it could be that as well.

 

I took off the accessory belt and timing covers and ran it. Video
However it looks fine. I put it all back together and it sounds almost like it could be coming from the rear of the engine facing the firewall. Any other ideas?

 

Monitor your battery level (plug-in the charger between runs) and buy a mechanic's stethoscope. Place it VERY CAREFULLY around the different NON-ROTATING points of the engine and determine the loudest point of this sound. Then check the surrounding parts for damage.

 

Sounds like the adjuster pulley bearings are bad.

 

did you find out what this was? sounds similar to the noise my tl is making