I'm inclined to believe it is a lifter. The 190's have a spring held ratchet as a tensioner, not the oil pressure held tensioner. Once the chain stretches enough for the spring to push out the tensioner out another click, it will ratchet out and stay. It cannot go back in. I fail to see how the spring tensioner can cause the noise mentioned while oil pressure is obtained.
BTW. Mine does the same. How can I determine which lifter is faulty?????
'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)