I have a very loud rattle when I first start my car up. But if goes away after a couple of seconds. Very quick, loud and then it's gone. I was wondering if this may be the tensioner?

The airpump bearing grinds for a good minute and then goes away so I know it's not that. This noise is different. I also know it is not the tensioner shock because I replaced that last year.

How can I test to see if it is the tensioner? The noise does not last long enough for me to pinpoint the location. Would a tensioner going out make constant noise? Or could it rattle hard just on start up?

If it is the tensioner, what are the steps to replacing it? Thanks.

1994 c280, 85k miles

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