Gotta be the reservoir, either the grommets or the hose that supplies fluid to the ABS unit. Both are cheap and replaceable-if you re-seat the reservoir, I suggest you drill a hole in the top of it and suck any/all fluid out-makes this job a LOT cleaner. Then replace the reservoir-it comes with the grommets you need from the dealer , and its cheap

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"If God had meant for us to walk, why did he give us feet that fit car pedals?" Sir Sterling Moss

Michael
2014 E63S Estate
2006 SLK55
1995 E500
1986 Porsche 944 turbo