Heard a strange vibrating noise from the timing belt section of the motor, like plastic vibrating, thought it was the timing belt. Took the cover off and sure enough every time i'd give it gas it would rub against the inside plastic cover. How do i tighten the timing belt and what is the right tension? Thanks...

 

retension the tensioner. honda is not specific about how taught it should be, but rule of thumb is 1" of deflection from cam to crank.

 

I'd retension it immediately. If it's that loose a little extra noise may be the least of your worries.