air bleeding RENAULT MEGANE SCENIC 1995 Service Repair Manual

Page
COOLING
Specifications
Filling - bleeding
Checking
Radiator
Diagram
Exhaust
General
Catalytic converter
Exhaust pipe assembly
Fuel tank
Fuel tank
Filler neck
Gauge
Pump and sender unit
Engine suspension
Suspended engine mountings
Engine mounting pads19-1
19-2
19-3
19-4
19-6
19-12
19-15
19-16
19-19
19-23
19-25
19-26
19-29
19-32 COOLING - EXHAUST- FUEL TANK -
ENGINE SUSPENSION
1916-1
16-9 STARTING - CHARGING
Alternator
Starter motor
16
IGNITION - INJECTION
IGNITION
Power module
Static ignition
Spark plugs
Injection
General
Location of components
Special notes on semi-sequential
injection
Special notes on sequential injection
Injection fault warning light
Engine immobiliser function
Computer configuration as a
function of the gearbox type
17
14-1
14-9
14-13
14-19
14-21
14-22 ANTIPOLLUTION
Fuel vapour recirculation
Oil vapour rebreathing
Exhaust gas recirculation (EGR)
Catalytic converter
Catalytic converter - oxygen sensor
Test for the presence of lead
14
17-28
17-29
17-32
17-33
17-34
17-36
17-39 IGNITION - INJECTION
(continued)
Injection strategy / automatic
transmission
Injection strategy / air conditioning
Idle speed correction
Idle speed adaptive correction
Richness regulation
Adaptive richness correction
Operating wiring diagram
17
Page
17-1
17-2
17-5
17-6
17-12
17-17
17-19
17-24
17-25
17-26
Contents

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

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.
14-8