2007 Tacoma 4.0 tick

OK guys this is NOT the regular 4.0 tick that our trucks (including mine from day 1) have. This is a different sound, a pretty loud ticking.
About 6 or so months ago my truck broke down on the freeway, with a misfire and my mechanic says when he pulled the spark plug out and ran the motor he says he say a piece of carbon come out of the chamber. Put the plug back in and was fine.
However ever since that, the engine has had a pretty loud tick I have a short video of it I'm gonna try to link to this so you can hear it, but the video does not do it justice. Any ideas of what it could be?
The moment I got my truck back from my mechanic I ran seafoam through it to try and clean out carbon build up but it really didn't smoke much at all, unlike my mom's car I did minutes after my truck and her car (corolla) left a thick cloud of smoke a block long and so thick couldn't see the street. My truck had a little smoke but nothing compared to hers and didn't leave anything while I took for test drive.

 

OK here it is
http://s200.photobucket.com/user/MonteCarlo-1972/media/Mobile Uploads/20141121_164014.mp4.html

 

if you go take a ride, floor it a couple times to get rpms up, then set it running for few minutes at idle in the driveway, does water start dripping from the tailpipe? maybe it was not carbon that flew out. the head gaskets are made of several thin layers of metal, maybe one of the layers has started to breakup a little, a piece that had come loose from the head gasket may have flown out when he did that.

a TINY leak in the head gasket will not set off a check engine light, but can pass a TINY amount of coolant that will end up coming out of the tail pipe.

 

Haven't noticed. It's cold in the morning so everyone's car has a little but nothing more than average