A vacuum leak at the Fuel Pressure regulator can cause poor fuel mileage.
A leak on the output of your fuel pump can do the same.
Just a couple of things that I've found over the years.

Stan Wilder

On Mon, 17 Mar 2003 22:10:28 +0000 peter hargreave
<phargreave@HOTMAIL.COM> writes:
I have an 85 Westfalia.  Over the past year, my van has gone from about
400 km per tank to arround 230 km per tank.  It is not leaking gas and I
have got the O2 sensor checked.  What else could cause such a drastic
reduction in fuel efficiency?  If any one could help it would be greatly
appreciated.  Besides being evironmentally unsound, gas has hit 91 here
in BC.
Thanks in advance.
All the best,
Pete

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