Page 196 of 2492

ANTIPOLLUTION
Fuel vapour recirculation
14
OPERATING PRINCIPLE
The fuel tank is connected to the outside through
the canister.
Fuel vapour is retained by the active carbon in the
canister.
So that the fuel vapour contained in the canister
does not evaporate into the atmosphere when
the fuel tank is opened, a valve isolates the canis-
ter from the fuel tank when the fuel filler cap is
removed.
The fuel vapour contained in the canister is elimi-
nated and burnt by the engine.
To do this, a pipe connects the canister and the in-
let manifold. A solenoid valve is located on this
pipe to control bleeding of the canister.
The operating principle for the solenoid valve is to
give a variable passage diameter (depending on
an RCO signal from the injection computer).
The variation in the selection of passage diameter
for the fuel vapour in the solenoid valve results
from the balance between a magnetic field crea-
ted by the feed to the coil and the force of a re-
turn spring ensuring the valve remains closed.
CONDITIONS FOR CANISTER BLEEDING
During richness regulation
Coolant temperature greater than:
- + 55°C (F3R engine),
- + 15°C (K7M engine),
- + 70°C (E7J engine).
Air temperature greater than:
- - 10°C (F3R engine),
- + 10°C (K7M engine),
- + 20°C (E7J engine).
No load position not recognised (if the throttle
position sensor is faulty, the non-recognition of
the no load condition is replaced by an engine
speed condition
engine speedR > 1500 rpm.).
Outside richness regulation
No load position not recognised.
Coolant temperature less than +15°C for
F3R and
K7M engines (no condition for E7J engine).
If the oxygen sensor is faulty, the canister is bled
when there is no no load.
The cyclical opening ratio for the canister bleed
solenoid valve may be seen using the XR25 and
#23. The solenoid valve is closed for #23 = 0.7 %
(minimum value) except for E7J engines (no #23).
14-4
Page 197 of 2492
99782S
99218S
ANTIPOLLUTION
Fuel vapour recirculation
14
LOCATION - REMOVAL
CANISTER BLEED SOLENOID VALVE
K7M engine
The valve is mounted on the inlet manifold.
99361S
F3R engine
The valve is mounted at the front right on the
same mounting as the computer.E7J engine
The valve is mounted on the inlet manifold.
14-5
Page 200 of 2492

ANTIPOLLUTION
Fuel vapour recirculation
14
CHECKING THE OPERATION OF THE CANISTER
BLEED VALVE
A malfunction in the system could cause the idle
speed to be unstable or the engine to stall.
Check the circuit conforms (see diagrams).
Take care to check that the pipe marked "CAN"
on the solenoid valve is connected to the canister.
Check the condition of the pipes up to the fuel
tank.
97393R4
1Inlet manifold
2Canister bleed solenoid valve
3Canister
4Fuel tankAt idle speed, check by connecting a pressure
gauge (- 3 ; +3 bars) (Mot. 1311-01) to the "CAN"
outlet on the solenoid valve, that there is no
vacuum (in the same manner, check the command
value read by the
XR25 using #23 remains at a
minimum X = 0.7 % for F3R and K7M engines). Is
there a vacuum ?
YESIgnition off, use a vacuum pump to apply a
vacuum of 500 mbars to the solenoid valve
at (C). The vacuum should not vary by more
than 10 mbars in 30 seconds.
Does the pressure vary?
YESThe solenoid valve is faulty, renew
it. Air must also be blown into the
pipe connecting the solenoid valve
to the canister to eliminate any
particles of active carbon.
NOThere is an electrical fault - check
the circuit.
NOUnder bleeding conditions (engine not at
idle speed, engine warm), there should be
an increase in the vacuum (at the same
time, the value for #23 on the XR25 should
increase forF3R and K7M engines).
The fuel tank breather pipe can also be checked.
After removing the filler cap, use a vacuum pump
to apply a vacuum to the pipe at (B). If a vacuum
can be applied to the pipe this shows that the
overfilling valve is correctly sealed.
As soon as the filler cap is replaced, however, the
vacuum should disappear quickly as the pipe is no
longer blocked and the internal degassing
chambers in the fuel tank are connected.
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Page 201 of 2492
ANTIPOLLUTION
Oil vapour rebreathing
14
E7J engine
PRESENTATION OF THE CIRCUIT
94563R3
Upstream rebreathing circuit
1Take-off on air filter
2Filter - nozzle connecting pipe
3 6 mm diameter nozzle
Downstream rebreathing circuit
4 1.5 mm diameter nozzle
5Restriction to T union connecting pipe
6T union
7Take-off on inlet manifold
8To canister bleed
CHECKING
To guarantee correct operation of the
antipollution system, the oil vapour rebreathing
circuit should be kept clean and in good
condition.
Check the nozzles are present and correct.
14-9
Page 202 of 2492
99231R
ANTIPOLLUTION
Oil vapour rebreathing
14
K7M engine
PRESENTATION OF THE CIRCUIT
1Cylinder head
2Manifold
3Oil vapour rebreathing pipe connected upstream of the throttle body (the circuit is used for average and
high loads)
4Oil vapour rebreathing pipe connected downstream of the throttle body
5Fuel vapour recirculation pipe
6T piece connecting the oil vapour rebreathing pipe (4) and fuel vapour recirculation pipe (5)
7Oil vapour rebreathing pipe and fuel vapour recirculation pipe
8Air duct
95 mm diameter nozzle
CHECKING
To guarantee correct operation of the antipollution system, the oil vapour rebreathing circuit should be kept
clean and in good condition.
Check the nozzle is present and correct.
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Page 203 of 2492
DI1407-1
ANTIPOLLUTION
Oil vapour rebreathing
14
F3R engine
PRESENTATION OF THE CIRCUIT
1Inlet manifold
2Throttle body
3Oil vapour rebreathing pipe (connected to throttle body)
4Oil decanter
5Oil vapour rebreathing pipe from the engine to the decanter
The restrictions upstream and downstream of the oil vapour rebreathing system are moulded into the
throttle body.
CHECKING
To guarantee correct operation of the antipollution system, the oil vapour rebreathing circuit should be kept
clean and in good condition.
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Page 204 of 2492
ANTIPOLLUTION
Oil vapour rebreathing
14
F8Q engine
PRESENTATION OF THE CIRCUIT
DI1410
1Oil vapour decanter
To guarantee correct operation of the antipollution system, the oil vapour rebreathing circuit should be
kept clean and in good condition.
The oil vapour rebreathing pipes have no restrictions.
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Page 205 of 2492
ANTIPOLLUTION
Exhaust gas recirculation (EGR)
14
K7M engine
This system is only fitted to the K7M 703 engine.
PRESENTATION OF THE CIRCUIT
99377R
1Cylinder head
2EGR solenoid valve (operated by an RCO
signal)
3Mounting for EGR solenoid valve
4Vacuum reservoir
5Filter unit
6Inlet manifold
7Exhaust manifoldAExhaust gas to EGR solenoid valve
BExhaust gas circulation to inlet manifold
14-13