the 1998 C230 - I also have one - has NO power steering filter.
Best to suck out power steering from reservior every six months and replace with fresh fluid.
Also listen carefully to the accessory belt pulley tensioner, i's the black miniature shock/damper looking thing behind and below the power steering resrvior. That tensioner is know to fail and make noise - though the noise you describe doesn't exactly match.
|