The picture looks like a W210 car. I thought they began in '96. If it IS a '96, be careful what you ask for, you might get it. I had a '96 E300D that I bought new. The induction manifolding was variable length and quite problematic. The M104 wasn't bullet proof, but it was worked out pretty well by that point.

The only way I know to find your noise is to pull the belt and turn every pulley by hand. Idler pulleys seem to be more of a swishy rattling sound. A whining noise would typically be a compressor or steering pump. At least in my experience.

Didn't the first year 210 cars have the M104? If so, you can loosen the alternator, pull out one of the bolts and lean it over enough to get the belt off and back on without fooling with the tensioner.

Nice car, nice dog. Keep us posted.

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2001 SLK 320 six speed manual
2014 Porsche Cayenne six speed manual

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