Page 1153 of 2490
tank vapou
r pressure.
Canister purge operation is as described in Evaporative Emissions Control.
Evaporative Flange Assembly
The evaporative loss flange assembly is fitted to the top of the tank via a seal and locking ring. The assembly is removeable
complete with the fitted components.
The vapour vent / rollover valve and pressure sensor are a pu sh fit via sealing grommets. The fuel pump connector is push
fitted and crimped into a location tu be on the underside of the flange.
It
em
Par
t Number
De
scription
1—Vapour vent /
rollover protection valve
2—Pres
sure sensor
3—Fue
l pump connector
4—Evaporative loss flange locking rin
g
Page 1154 of 2490
The pressure co ntrol val
ve is fa
stened by adhesive to the lefthand side of the tank. It is a non-serviceable component.
Ite
m
Par
t
Number
De
scr
iption
1—Pressure control
valve
2—Fill
er neck pressure sensing pipe
3—Vapour pipe fro
m ta
nk
4—Vapour outlet pipe to u
n
derfloor canister
P
r
essure Control Valve
Page 1155 of 2490

T
he canisters are fixed to the underside of the vehicle either
directly or via semi-enclosed mounting brackets. Two fixing
bolts are used at the front of the canister(or bracket) and a single rear bolt supports the canister and the canister close
valve (CCV).
The vapour pipes to the canisters, other than the CCV, use multi-tang connectors which are push fitted and pulled out
without the use of tools.
The canister close valve has a stub pipe with 'O' ring seal wh ich is a simple push fit into the canister. A mounting bracket on
the canister close valve enables it to be secured to the underbody via the canister rear mounting bolt.
A hose connects the CCV to the bracket mounted adaptor into which the vent system air filter is screwed.
It
em
Par
t Number
De
scription
1—C
harcoal canister (righthand) in mounting bracket
2—Cani
ster close valve (showi
ng canister stub pipe)
3—Ai
r filter
4—Q
uick-fit vapour inlet connector
5—Cani
ster close valve electrical connector
Canister, CCV an
d Fittings
Page 1156 of 2490

The system has the
following features :
o
n
-board refueling vapour recovery (ORVR) to reduce the fu
el vapour vented directly to atmosphere from the filler
nozzle when refueling.
two ch arcoal
canisters are connected in series to reduce th
e concentration of fuel in vapour vented to atmosphere.
a t
ank pressure sensor and canister close
valve are fitted to allow the on-board di agnostic facility to test for leaks in
the fuel and evaporative system.
The canister close valve is a solenoid operated device controlled by the ECM. The valve is normally open and is closed only
during the leak test sequence.
The fuel pressure sensor is fitted to th e evaporative loss flange and provides a volt age to the ECM which is proportional to
tank vapour pressure.
Op era
tion of ORVR System
The ORVR system enabl
e
s fuel vapour generated during re-fueling to be collected by
the charcoal canisters. During normal
running of the vehicle, the vapour is collected and purged in the same way as for non-ORVR systems.
Ite
m
Par
t
Number
De
scr
iption
1—Grade vent
valve outl
et
2—Vapour outl
et from fil
l level vent valve (FLVV)
3—F
L
VV pressure relief valve outlet pipe
4—N
a
rrow diameter fuel filler tube
5—Charcoal can
i
sters
6—Cani
st
er close valve
7—Vent pi
pe ai
r filter
8—Vapour pipe
conn
ecting canisters
9—Canister purge ou
tlet pipe
10—EVAP canister purge v a
lve (engine bay)
11—Vacuu
m
control signal from induction elbow
12—EVAP pu
rge valve outlet to induction elbow
Running Loss with On-board R
efuelin
g Vapour Recovery (ORVR) System
Page 1157 of 2490

The OR
VR system features are :
N
arrow fuel filler pipe and tank check valve.
Fue
l level vent valve (FLVV) fitted to the evaporative flan
ge and consisting of a two stage shut-off valve with rollover
protection and a pressure relief valve.
Grade ven
t valve with rollover protection, fitted to the ev
aporative flange and with an outlet pipe connected to the
FLVV vapour outlet pipe.
Large bore vapour vent pipes.
The fuel filler pipe has a reduced diameter between the nozzle guide and the tank, providing a liquid seal when re-fueling
and preventing the fuel vapour venting directly to atmosphere. There is no breather tube fitted between the tank and the
filler nozzle. To prevent spit back when re-fueling, a check valv e is fitted at the lower end of the filler pipe inside the tank
(see Figure).
During re-fueling, the tank is vented to atmosphere via the fuel level vent valv e (FLVV), large bore vapour pipes and the
charcoal canisters. The FLVV incorp orates a float valve which is closed by the rising fuel level, creating a back pressure and
causing the fuel delivery to stop. In the closed position, the FLVV also sets the fuel level.
With the FLVV closed (tank full), any increase in pressure or overfilling is relieved by a separate rollover protected grade
vent valve. The outlet from this valve feeds into the main FLVV vapour outlet pipe, bypassing the closed FLVV.
When the fuel level is below full, the FLVV opens to allow unrestricted venting via the canisters.
A pressure relief valve is incorp orated into the FLVV assembly and has an outlet pipe to the filler nozzle,. If a blockage or
other restriction (eg, canister close valve failing in the closed position) occurs in the vapour vent system, the pressure reli ef
valve opens to allow venting to atmosphere via the filler nozzle guide and fuel filler cap.
Canister purge operation is as described in Evaporative Emissions Control.
Filler Tube and Check Valve
Page 1158 of 2490

The fuel fil
ler cap is the same as
that used on non-ORVR systems.
The check valve assembly is a push fit into the end of the fuel filler tube and is accessible with the evaporative flange
removed. The valve has a light spring load ing and opens under the inflow of fuel.
ORVR Evaporative Loss Flange Assembly
The evaporative loss flange assembly is fitted to the top of the tank via a seal and locking ring arrangement identical to that
used for non-ORVR systems. The assembly is re moveable complete with the fitted components.
The fuel level vent valve (FLVV) is mounted in the ELF assembly via a bayonet fitting : it is turned approximately 90 °
clockwise to release. The grade vent valve and pressure sensor are push in fits via sealing gromme ts : note that, due to the
tight fit, removal of these components may require cutting the grommets. The fuel pump connector is push fitted and
crimped into a location tube on the underside of the flange.
It e
m
Par
t
Number
De
scr
iption
1—An
ti-s
urge valve
2—Pressure rel
i
ef pipe
3—Check v
a
lve
It
e
m
Par
t
Number
De
scr
iption
1—Fi
ll
level vent valve (FLVV) /
pressure relief valve assembly
2—Pres
sure
sensor
3—Grade vent
valve
4—Fue
l
pump connector
5—Lockin
g rin
g
6—Evaporative loss flange (ELF)
7—Seal
8—F
u
el pump link lead
Page 1159 of 2490

T
he canisters are fixed to the underside of the vehicle either
directly or via semi-enclosed mounting brackets. Two fixing
bolts are used at the front of the canister(or bracket) and a single rear bolt supports the canister and the canister close
valve (CCV).
The vapour pipes to the canisters, other than the CCV, use multi-tang connectors which are push fitted and pulled out
without the use of tools.
The canister close valve has a stub pipe with 'O' ring seal wh ich is a simple push fit into the canister. A mounting bracket on
the canister close valve enables it to be secured to the underbody via the canister rear mounting bolt.
A hose connects the CCV to the bracket mounted adaptor into which the vent system air filter is screwed.
It
em
Par
t Number
De
scription
1—C
harcoal canister (righthand) in mounting bracket
2—Cani
ster close valve (showi
ng canister stub pipe)
3—Ai
r filter
4—Q
uick-fit vapour inlet connector
5—Cani
ster close valve electrical connector
Canister, CCV an
d Fittings
Page 1160 of 2490
Ite
m
Part
Number
Descr
iption
1—Fu
el tank pressure sensor (if applicable)
2—Engine m
anagement ECU
3—EVAP canister purge va
lve
4—EVAP ca
nister close valve (if applicable)
5—Engine
mana
gement fusebox - IGN supply
Circuit diagram
,
evaporative emissions systems