The vacuum line acts as a signal to the pressure regulator.
The amount of vacuum present will affect the actual rail pressure.

Low vacuum raises the pressure, which equates to more fuel going into the cylinder.

Something doesn't jibe WRT your description. It shouldn't be that diffucult to install the line on the regulator.


Jim

__________________
14 E250 BlueTEC black. 45k miles
95 E320 Cabriolet Emerald green 66k miles
94 E320 Cabriolet Emerald green 152k miles
85 300TD 4 spd man, euro bumpers and lights, 15" Pentas dark blue 274k miles