Originally Posted by HAMMER DOWN
Check and adjust the clearance between timing belt and timing belt guides. There is 5 guides, one for each cam gear & one for the crank. Clearance should be 1.0mm +\- 0.5mm (0.039" +\-0.020")
^That's correct. I guess you have already adjusted the clearances but here is a TB guide I followed over on Youtube. This guy gives a great tip starting at 12:05. He also shows how he adjusts those guides.
Out of curiosity, how old is your timing belt tensioner? It is somewhat rare but mine did this
at 51000 miles
. I was EXTREMELY lucky I did not bend my valves..