M103 -- symptoms of tensioner shock dead?

[ps2cho]

I have a clacking noise that clears up after a little driving that is coming somewhere on the belt drive system. I tried scoping in and I cannot really tell if the tensioner shock is the one making the noise or not.

I can't tell because when I touch it with anything, its moving up and down I can't get a reading.
Is a "clacking" noise symptomatic of the tensioner shock getting towards end of life or should I look elsewhere?

And also, can it be replaced without loosening tensioner device? I'd like to get away with not touching the tensioner device itself.

Thanks guys