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striker and the fuel cap stowage magnet.
The fuel bowl, retained around the filler neck by a clip, containing a drain tube filter located
overthe mating drain tube,
is rubber moulded onto a steel armature and fitted to the BIW decking panel. by five M5 nuts.
The fuel lid latching assembly fitted to the metal armature of the fuel bowl by an M5 nut, includes the locking pin and
the operating actuator.
The actuator operates from the central locking system driven by the Security and Locking Control Module (SLCM).
The fuel tank, mounted across the vehicle behind the passenger compartment rear bulkhead, is held in position by two
retaining straps, tightened by two M5 fixing arrangements.
VI2 engined vehicles are equipped with two fuel pumps located inside the tank. They are regenerative turbine pumps
supplied by Nippon Denso. Nominal operating pressure is 3 bar above the manifold depression and pump delivery
is 90 litres/hour minimum at 13.2 volts, 3 bar outlet pressure. The pump draws a nominal current of 7 amperes at 13 volts, 3 bar outlet pressure, ambient temperatures. Built in to the pump assembly is a over-pressure relief valve which
blows at 4.5 - 8.5 bar.
Fuel is drawn by the pumps from the fuel tank and is then supplied to the fuel rail via a
70 micron filter and the fuel
feed line connected in series by fuel filter.
The amount of fuel being injected into the engine is controlled by the fuel injectors combined with the engine control
module (ECM).
Any excessive fuel flowing through the system, is returned to thefuel tankvia the fuel regulator valve mounted on the
fuel rail, the fuel return line and the check valve also located inside the tank.
The two filters prevent contaminants from entering the fuel rail and possible damage to the fuel injectors, the engine,
the pump and underfloor filter.
The second fuel pump is controlled by the engine control module
(ECM) and works of a mapped fuel map. The pumps
'switch on' time depends on the fuel requirement which is depending on the engine load.
The fuel lines are made up of an assembly, combining steel underfloor pipes and flexible conductive anti
-permeation
tubing. In order to perform speedy remove and refit operations, the underfloor steel lines are linked through the engine
bay bulkhead to theflexibletubing, leading to the fuel rail and the fuel regulator by using positive sealing, quick
fit type
connectors. The same type connectors, are used to connect the fuel feed and return line to the fuel tank.
Connectors used inside the engine bay, are of different sizes to correspond with the difference in pipe diameter, where
- as the connectors for the feed and return lines at the fuel tank are the same size.
Except for the return line connector at the fuel tank, two release tools, one for each size of connector, are required to
release all remaining connectors.
Fuel, Emission Control & Engine Management (V12)
5.2.2 GENERAL DESCRIPTION
WARNING: WORKING ON THE FUEL SYSTEM RESULTS IN FUEL AND FUEL VAPOUR BEING PRESENT IN THE AT- MOSPHERE. FUEL VAPOUR IS EXTREMELY FLAMMABLE, HENCE GREAT CARE MUST BE TAKEN WHILST
WORKING ON THE FUEL SYSTEM. ADHERE STRICTLY TO THE FOLLOWING PRECAUTIONS:
PO NOT SMOKF, IN THE WORK AREA.
DISPLAY 'NO SMOKING
' SIGNS AROUND THE AREA.
ENSURE THAT A
CO2 FIRE EXTINGUISHER IS CLOSE AT HAND.
ENSURE THAT DRY SAND
IS AVAILABLE TO SOAK UP ANY FUEL SPILLAGE.
EMPTY FUEL USING SUITABLE FIRE PROOF EQUIPMENT INTO AN AUTHORIZED EXPLOSION PROOF
CONTAINER.
DO NOT EMPTY FUEL INTO A PIT.
ENSURE THAT WORKING AREA IS WELL VENTILATED.
ENSURE THAT ANY WORK ON THE FUEL SYSTEM
IS ONLY CARRIED OUT BY EXPERIENCED AND WELL
QUALIFIED MAINTENANCE PERSONNEL.
The fuel filler assembly, supplied complete with serviceable lid, hinge and hinge spring, is fixed to the Body-in-White (BIW) decking panel by two M5 nuts. Additional parts of the assembly comprise a adjustable rubber buffer, a snap-in
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Fuel, Emission Control 8t Engine Management (V12)
The connectors are released by pushing the tool in to the female half ofthe connector and at the same time disengaging
the latches.
Viton hosing surrounds the tubing, thus preventing any po
- tential damage from fire and other matters.
The conductive anti
-permeation tubing does not return to
its original shape after being deformed. Therefore do not
clamp (eg. for sealing purposes prior to disconnection of
tubes) as this damages the fuel pipes.
The evaporative
loss control system, prevents unprocessed
vapour emitted from the fuel tank from entering the atmos- phere.
The tank pressure control (Rochester) valve is installed be
- tween the fuel tank and the carbon canister. lt is normally
closed, but open during engine operation, venting the va- pours from the fuel tank to the carbon canister.
The purge valve is controlled by the engine control module
(ECM) and is linked to the carbon canister.
Fig.
1 Quick-fit Connector and Release Tool
X300 VSM Issue 1 August 1994 4
Page 95 of 521
Fuel, Emission Control & Engine Management (V12)
9
Fig. 1
Disconnect vacuum hose (1 Fig.1) from cruise control actuator (2 Fig.1).
. Disconnect vacuum hose (3 Fig.1) from fuel pressure regulator.
Disconnect throttle control rods from throttle pulley assembly ball pins (4 Fig.1).
. Reposition throttle control rods to inner wings.
. Disconnect cruise control rod from throttle pulley assembly ball pin (5 Fig.1).
. Undo and remove bolts securing fuel rail.
. Reposition cruise control rod below throttle pulley assembly.
. Remove cruise control actuator / bracket assembly and fixings (6 Fig.1).
. Disconnect injector harness plugs (7 Fig.1).
Disconnect throttle potentiometer multi-plug (8 Fig. 1)
. Remove throttle pulley bracket assembly and fixings (9 Fig.1)
. Remove injector harness plastic clips (IO Fig.1) from fuel rail.
. Remove fuel rail / injector assembly (1 1 Fig.1).
Issue 1 August 1994 6 X300 VSM
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Fuel, Em i ssion Control & Engine
Management
J19 L76
Fig. 1
Remove injector to fuel rail retaining clips (1 Fig.1).
. Remove injector (2 Fig.1).
Remove fuel regulator retaining plate and fixings (3 Fig.1).
. Remove fuel regulator (4 Fig. 1 ).
. Remove and discard ‘0’ ring seals.
Refit in the reverse order of the removal procedure.
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Fuel, Emission Control & Engine Management (V12)
5.2.4 PURGE CONTROL VALVE, RENEW
SRO 17.15.42 'A' BANK
SRO 17.15.43 'B'BANK
SRO 17.15.44 VEHICLE SET
Fig. 1
Remove
. Remove the left-hand headlamp relay cover (1 Fig.l), see Section 15.
. Remove the left-hand air cleaner element (2 Fig.1).
. Remove the right-hand air cleaner assembly (3 Fig.1).
Remove air box mounting bracket (4 Fig.1).
. Disconnect 'A' bank purge valve multi-plug (5 Fig.1).
. Release securing clip (6 Fig.1).
. Disconnect all hoses (7 Fig.1) from valve.
. Remove valve (8 Fig.1).
Refit the purge valve in the reverse order of the removal procedure.
Issue 1 August 1994 8 X300 VSM
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Fuel, Emission Control & Engine Management (V12) ~~ ~
5.2.5
SRO
18.30.74 VEHICLE SET
IDLE SPEED CONTROL VALVE/ GASKETS, RENEW
SRO
18.30.73 VALVE- RIGHT HAND
SRO 18.30.76 GASKET
- RIGHT HAND
SRO
SRO 18.30.75 GASKET- LEFT HAND
18.30.72
VALVE
- LEFT HAND
Remove
. Disconnect battery.
. Drain coolant from radiator, see Section 4.2.
. Disconnect idle speed control valve multi-plug.
Disconnect all hoses linked to the idle speed control valve.
. Remove valve.
. Remove gasket.
Refit in the reverse order of the removal procedure.
5.2.6 FUEL CUT-OFF INERTIA SWITCH, RENEW
SRO
18.30.35
Remove
. Disconnect battery.
. Remove the 'A' post lower trim pad.
= Remove the EMS control module, see Section 15.
. Disconnect vehicle harness through-panel connector.
. Disconnect inertia switch multi-plug (Fig. 2).
9 Remove switch.
Refit in the reverse order
of the removal procedure. Fig.
1
Fig. 2
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Exhaust System (AJ16)
1 2
Fig. 1 Plan View (AJ16 Supercharged)
4 5
i
J30-224
The only visible difference between the normally aspirated engine's exhaust system and the supercharged version (Fig.1) is that the downpipe for the supercharged engine (Fig.1 and next page) is slightly shorter.
The remove
& refit procedures are the same as for the AJ16 normally aspirated.
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Also look for loose and rusted flange connections, loose or damaged exhaust shields
or clamp and loose or broken exhaust outlet pipe brackets.
6.1.2.1 Symptom Chart
I Condition I Possible Cause
Noises and exhaust fumes Exhaust leak.
Misaligned exhaust.
Loose clamps or fasteners.
Restricted exhaust system.
Electronic engine controls.
Fuel System.
Restricted exhaust system.
Engine lacking
power Ignition system.
Exhaust System (AJ16)
6.1.2 DIAGNOSIS AND TESTING
m: THE NORMAL OPERATING TEMPERATURE OF THE EXHAUST SYSTEM IS VERY HIGH. NEVER ATTEMPT
TO SERVICE ANY PART OF THE SYSTEM UNTIL IT HAS COOLED. EXHAUST GASES CONTAIN CARBON
MONOXIDE WHICH CAN BE HARMFUL TO HEALTH AND ARE POTENTIALLY LETHAL. LEAKS MUST BE
REPAIRED IMMEDIATELY.
NEVER OPERATE THE ENGINE
IN ENCLOSED AREAS.
External leaks in the exhaust system are often accompanied by noises and exhaust fumes, therefore a visual inspection
usually detects the location of the leak. When checking for exhaust leakage or noise, inspect the entire system for
burned
-out holes, loose or corroded clamps, muffler or exhaust inlet pipe.
Examine the under body for greyish
-white or black exhaust soot which indicates the exhaust leakage at that point.
The effect of a small leak can be magnified by holding a rag over the tailpipe outlet while listening to the leak.
If this is carried out, ensure that gases are not inhaled
-see WARNING.
When testing for a rattle or vibration condition it is helpful to use a rubber mallet. Tap on the exhaust components to
simulate the bouncing action of the exhaust while watching for exhaust-to-body /chassis contact.
6.1.2.2 Test A, Exhaust Leakage or Noise
Test Step
Step
1A Clamps and Brackets
Check for broken or loose clamps and/or exhaust
outlet pipe frame brackets.
Are clamps and exhaust outlet pipe frame brackets
OK?
Step 2A System Components
Check catalytic converters, muffler.
Are system components OK?
Step 3A Exhaust Manifold
Inspect exhaust manifold for loose fasteners and
cracks.
Is exhaust manifold OK?
Action
Refer to Test Step 1A.
Go to Test Step IB, Restricted exhaust system test. .-
Go to Test Step 1B
Result Action
yes
1
Go to Step 2A
no Service and renew as necessary.
Restart engine.
If noise still exists
go to Step 2
yes Go to step 3A
no Renew exhaust outlet pipe frame brackets, exhaust
inlet pipe and/ or muffler as necessary.
If noise still persists, go to Step 3
yes
no Go to Test Step 1B Restricted exhaust system test.
Tighten fasteners or renew exhaust manifold.
X300 VSM 5 Issue 1 August 1994