No Flow through Pressure Regulator

Marc Boucher mboucher70 at
Wed Feb 4 16:35:28 EST 2004

Today's update:

1.) Cleaned the DPR thoroughly...found a plastic hose that fit snugly into
one hold of the DPR and can confirm that there is clear passage through the
DPR...i.e. it is not clogged.

2.) Energized fuel pump, saw fuel flowing out one of the holes from the fuel
distributor that goes to the DPR.
3.) Reattached DPR.
4.) Detached return hose.
5.) Energized fuel pump.  Same result as before.  No output from return
hose..Pump slows to a crawl as pressure builds up with no where to go.
6.) Detached, small pipe at the pressure regulator.  Energized fuel pump.
Confirmed flow out of pipe.
7.) Reattached small pipe and detached thicker pipe at the pressure
regulator.  Energized fuel pump.  Confirmed flow out of pipe.

Thus fuel distributor and both lines that flow into the pressure regulator
are flowing but nothing is coming out of pressure regulator.  Thus either
the pressure regulator is clogged or bad, or the fuel pump isn't pumping
sufficient pressure or both.

I've filled the pressure regulator with carb cleaner and have it sitting in
a sealed glass container.  I'll leave it soaking overnight and reattach
tomorrow.  Someone mentioned that they had an adjustment screw.  This one
does not.  And its the only part that I've seen that doesn't have "Bosch"
(or any other brand) stamped on it.  One end attaches to a plastic hose that
leads to a large container near the right fender.  I assume that fills with
air in order to keep pressure when the car is shut off?  I'm assuming
there's no benefit to filling that end of the regulator with carb cleaner.


More information about the quattro mailing list