Just an update. Ended up having to take the car to a shop as I could not find the leak. I was paranoid the high pressure fuel pump let go......turns out one of the fuel return lines buried under all the other stuff behind the engine had let go. $7 part, $135 in labor to get to it!

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2012 Mercedes ML350 Bluetec 102K (hers)
2005 Corvette 55K (fun car)
2002 VW Jetta TDI 238K (mine)
1998 Volvo S70 T5 Turbo 211K (kids)
1994 Ford F150 4WD 246K (firewood hauler)
1983 Mercedes 300D 384K (diesel commuter)