Hi JC, if you do a search on monovalves, you will find many hits. Unfortunately I don't think there is any magic repair on this one, despite many wishes for this - I don't think you can buy just the diaphragm or plunger with diaphragm. On older BMW's with basically the same monovalve type setup, you can buy just that piece fix things relatively cheaply.

Anyway, have a search and you may get some other inspiration for a bypass, etc. Or maybe I've overlooked an easy fix someone has found, it's been a long time since I looked at this.

Rgds,
Chris W.
'95 E300D, 391K

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