In a message dated 9/20/05 1:02:11 PM, shepherdsond@METRO.DST.OR.US writes:

<< Am I correct in thinking that this is a classic O2 sensor failure (the
computer being
reset to default values when the ignition is cycled off and then on)? >>

No.  The computer retains the last value read at the OXS whenever the car is
shut down unless the OXS is disconnected with the ignition off.

The conductor, and so the input, to the computer from the OXS might be
shorted to ground either internally by way of its shielding at its connector or,
less likely, externally to the chassis.  This would cause the van to run very
rich and evidence of this, other than extremely poor drivability, would be large
amounts of black smoke from the exhaust.

If the car behaves as if it is running out of fuel or as if the fuel filter
is clogged then, perhaps, it is running out of fuel or the fuel filter is
clogged OR there is something queer about the throttle position switch.  Check the
function and set point of the off-idle throttle position switch.

George