A
fuel
surge
tank
(FST)
is
designed
to
prevent
fuel
starvation
to
the
engine
on
vehicles
with
inadequate
fuel
tank
baffling.
The
FST
fuel
pump(s)
feed
the
fuel
rail(s).
The
volume
of
fuel
inside
the
surge
tank
acts
as
a
buffer
to
always
keep
the
FST
pump
supplied
with
fuel.
This
volume
is
maintained
by
the
main
fuel
tank's
pump
as
well
as
the
fuel
returning
from
the
fuel
pressure
regulator.
Excess
fuel
in
the
surge
tank
is
returned
back
to
the
vehicle's
main
fuel
tank.
