1996 FIAT PUNTO Elect

4A*2 Fuel system - single-point petrol Injection models
1 The luel system referred to In this Section is defined as the tank-mounted fuel pump, the fuel litter, the throttle body and pressure regulator components, and the metal pipes and flexible hoses of the fuel lines between these components. All ihese contain fuel which will be under pressure while the engine Is running and/or while tha Ignition is switched on. The pressure will remain for some time after tho ignition has been switched off, and must be relieved before any of these components are disturbed (or servicing work. 2 Disconnect the battery negative terminal (refer to D/sconnecf/ngr the battery in the Reference Section of this manual), 3 Place a container beneath the relevant connection/union to be disconnected, and have a large rag ready to soak up any escaping fuel not being caught by the container. 4 Slowly loosen the connection or union nut (as applicable) to avoid a sudden release of pressure, and wrap tho rag around the connection to catch any fuel spray which may be expelled. Once the pressure is released, disconnect the fuel line, and Insert plugs to minimise fuel loss and prevent the entry of dirt Into the fuel system.
9 Inlet manifold -removal and refitting ^
Note: Refer to the warning given In Section 1 before proceeding.
Removal 1 Remove the throttle body assembly as described in Section 5. 2 Drain the cooling system as described in Chapter 1A. 3 Disconnect the winng connector from the coolanl temperature sensor (situated on the left-hand sidB of the manifold). 4 Undo the bolt securing the accelerator cable mounting bracket to the manifold, and position it clear of the manifold. 5 Slacken the retaining clip and disconnect tha coolant hose from the rear of the manifold. 6 Disconnect the brake vacuum hose. 7 Undo the seven manifold retaining nuts and
10.2 The diagnostic connector la located behind the ECU bolts, and remove (he manifold from the engine. Remove the gasket and discard It; a new one should be used on refitting.
Refitting 8 Refitting is a reverse of the removal procedure, noting the following points: a) Ensure that the manifold and cylinder head mating surfaces are clean and dry, and fit a nev/ manifold gasket. Refit the manifold and securely tighten Its retaining nuts. b) Ensure that all relevant hoses are reconnected fo their original positions and are securely held (where necessary) by the retaining clips. c) Refit the throttle body assembly with reference to Section S. d) On completion, refill the cooling system as described In Chapter 1A.
correctly adjusted, and that the engine breather hoses are clear and undamaged. 2 If these checks fall to reveal the cause of the problem, the vehicle should be taken to a suitably-equipped Fiat dealer for testing. A wiring block connector Is Incorporated In the engine management circuit, into which a special electronic diagnostic tester can be plugged; the connector is situated behind the ECU (see Illustration). The tester will locate the fault quickly and simply, alleviating the need to test all the system components Individually, which is a time-consuming operation that carries a high risk of damaging the ECU.
Adjustments 3 As mentioned above, the idle speed and mixture adjustment are all monitored and controlled by the ECU, and are not adjustable Experienced home mechanics with a considerable amount of skill and equipment (including a good-quality tachometer and a good-quality, carefully calibrated exhaust gas analyser) may be able to check the exhaust CO level and ihe idle speed. However, If thes* are found lo be in need of adjustment, the car must be taken to a suitably-equipped Flat dealer for testing using the special test equipment which is plugged into the diagnostic connector.
11 Unleaded petrol -general Information and usage
10 Fuel injection system - & testing and adjustment S
Testing 1 If a fault appears in the fuel injection system, first ensure that all the system winng connectors are securely connected and free of corrosion. Then ensure that the fault Is not due to poor maintenance; ie, check that the air cleanor fitter element is clean, the spark plugs are In good condition and correctly gapped, that tho valve clearances are
Note: The information given in this Chapter
is
correct at the time of writing. If updated Information is thought to be required, check with a Fiat dealer. If travelling abroad, consult one of the motonng organisations (or a similar authority) for advice on the fuel available. 1 All petrol models are fitted with a catalytic converter and must be run on unleaded fuel only - the fuel recommended by Flat is given In the Specifications of this Chapter. Under no circumstances should leaded fuei (UK 4-slar) be used, as this may damage the converter. 2 Super unleaded petrol (98 octane) can also be used in all models if wished, though there is no advantage in doing so.

4B*1
Chapter 4 Part B:
Fuel system - multi-point petrol injection models
Contents
Accelerator cable - removal, refitting and adjustment 4 Air cleaner and Inlet system • removal and refitting 2 Air cleaner filter element renewal See Chapter 1A Engine management system components (1242 cc, 8-valve engines) -removal and refitting 5 Engine management system components (1242 cc, 16-valve engines) - removal and refitting 6 Fuel filter renewal See Chapter 1A Fuel Injection system - depressurisation 9
Degrees of difficulty
Fuel injection system - testing and adjustment 11 Fuel pump and fuel gauge sender unit - removal and refitting 7 Fuel tank - removal and refitting 8 General Information and precautions 1 Idle speed and mixture adjustment See Chapter 1A Inlet air temperature regulator - removal and refitting 3 Inlet manifold - removal and refitting 10 Unleaded petrol • general Information and usage 12

Easy, suitable
for ^
novice with
Ittie experience ^
Fairly
easy,
suitable Jk for beginner
with
® someexperiencs ^
FaMycSffiait, J^ suitable
for
competent ^
DIY mechanic
^
Difficult
suitable
for experienced BY SJ mechanic ^

Very difficult,
^
suitable
for expert
DIY
jR or professional ^
Specifications
System type
Fuel system data Fuel pump type Fuel pump delivery rate: 1242 cc (8-vatve) engine 1242 cc (16-valve) engine Regulated fuel pressure: 1242 cc (8-vaive) engine: Pre-1998 models 1998 models onward 1242 cc (16*valve) engine Crankshaft TDC sensor resistance al 20°C Injector electrical resistance: Pre-1998 models 1998 models onward Injector duration (at Idle)
Recommended fuel Minimum octane rating
Torque wrench settings Coolant temperature sensor
Idle
control stepper motor Inlet manifold brake servo union Inlet manifold upper section-to-lower section (16-valve engines) Inlet manifold-to-cylinder head (16-valve engines) Inlet manlfold-to-cylinder head (8-valve engines) Throttle body to manifold Throttle potentiometer
Weber-Marelli integrated multi-point fuel injection/ignition system
Electric, immersed In fuel tank
120 Hires/hour minimum 110 litres/hour minimum
2.5 bars 3.5 bars 3.0 bars 650 to 720 ohms
16.2 ohms 13.8 to 15.2 ohms 2.0 ms
95 RON unleaded
Nm Ibfft a 2 4 3 35 26 9 7 15 11 27 20 7 5 3 2

4A*2 Fuel system -
single-point
petrol Injection models
1 General information and precautions
General information The
LAW
Weber-Maretil multi-point Injection (MPI) system is a self-contained engine management system, which controls both the fuel injoction and Ignition (see Illustrations). This Chapter deals with the fuel Injection system components only - refer to Chapter 5B for details of the ignition system components. The fuel injection system comprises a fuel tank, an electric fuel pump, a fuel filter, fuel supply end return lines, a throttle body, a fuel rail with four electronic Injectors, and an Electronic Control Unit (ECU) together with its associated sensors, actuators and wiring. On pre-1998, 8-valve engines and all 16-valve engines, the fuel pump delivers a constant supply of fuel through a cartridge filter to the fuel rail, and the fuel pressure regulator (located on Ihe fuel rail) maintains a constant fuel pressure at the fuel Injectors and returns excess fuel to the tank via the return
line, This constant flow system also helps to reduce fuel temperature and prevents vaporisation. On later 8-valve engines, a returnless fuel system is used. With this arrangement, the fuel filter and fuel pressure regulator are an integral part of the fuel pump assembly located In the fuel tank. The regulator maintains a constant fuel pressure in the supply line lo the fuel rail and allows excess fuel to recirculate in the fuel tank, by means of a bypass channel, if the regulated fuel pressure is exceeded. As the fuel filler Is an integral part of the pump assembly, fuel filter renewal Is no longer necessary as part of the maintenance and servicing schedule. The fuel injectors are opened and closed by an Electronic Control Unit (ECU), which calculates the Injection timing and duration according to engine speed, throttle position and rate of opening, inlet air temperature, coolant temperature and exhaust gas oxygen content information, received from sensors mounted on the engine. The injectors are operated simultaneously (le not sequentially) and Inject half of the quantity of fuel required on each turn of the crankshaft. Inlet air Is drawn into the engine through
the air cleaner, which contains a renewable paper filter element. On 8-valve engines, the Inlet air temperature is regulated by a vacuum operated valve mounted in the air ducting, which blends air at ambient temperature with hot air, drawn Irom over the exhaust | manifold. Idle speed Is controlled by a stepper motor 1 located on the side of the throttle body. Cold storting enrichment is controlled by the ECU using the coolant temperature and Inlet air temperature parameters to Increase the Injector opening duration. The exhaust gas oxygen content it constantly monitored by the ECU via the Lambda/oxygen sensor, whioh Is mounted in the exhaust downpipe. The ECU then uses this Information to modify the Injection timing and duration to maintain the optimum air/fuel ratio. An exhaust catalyst is fitted to all models. The ECU also controls the operation of the activated charcoal filler evaporative loss system - refer to Chapter 4D for further details. It should be noted that fault diagnosis of the IAW Weber-Marelll system Is only possible with dedicated electronic test equipment.
1.1a IAW Weber-Marelii multt-point Injection (MPi) system (8-valve engines) f Fuel
tank
7 Air
cleaner
13 Coolant temperature sensor 19 Diagnostic socket 2 Fuel pump 8 Fuel vapour trvp 14 Intake air temperature 20
EVAP
solenoid 3 Filter (pre-1998 models) 9 Idle control stepper motor sensor 21 Lambda/oxygen sensor 4 Fuel
rail
10 Manifold absolute pressure 15 Duel
relay
22 Rev counter 5 Pressure regulator
(pre-1998
sensor 16 Ignition colls 23 IAW failure warning light models)
11 ECU
17 Rpm and TDC sensor 24 Anti-refhjx
valve
6 Injectors 12 Throttle position sensor 18 Spark piugs

4A*2 Fuel system -
single-point
petrol Injection models
17 Have an assistant depress the accelerator pedal and check that the throttle cam opens luily and returns smoothly to its stop. If necessary, reposition the spring clip In the next outer cable groove and recheck the throttle operation. 18 Refit the remainder of the disturbed components.
5 Engine management
system
^ components
(1242
cc, 8-vatve § engines) -
removal and refitting
^
Note: Refer to the warning given In Section T
before
proceeding.
Throttle body assembly
Removal 1 Remove the air cleaner and inlet air duct as described in Section 2. 2 Disconnect the wiring connectors from the throttle potentiometer, the idle control stepper motor and the inlet air temperature sensor. 3 Slacken the accelerator cable locknuts, then disengage the inner cable from the throttle cam and free the outer cable from its retaining bracket. Position the cable clear of the throttle body. 4 Unclip and disconnect the EVAP purge valve hose, and Ihe MAP sensor hose from the rear of the throttle body then, where applicable, disconnect the fuel pressure regulator vacuum hose from the front of the throttle body. 5 Slacken and remove the four bolts securing the throttle body assembly to the inlet manifold, then remove the assembly along with its insulating spacer. Refitting 6 Refitting is a reversal of the removal pro-cedure. bearing in mind the following points: 4! Examine the Insulating spacer for signs of damage, and renew If necessary. b) Ensure the throttle body, inlet manifold and insulating spacer mating surfaces are clean and dry, then fit the throttle body and spacer, and securely tighten the retaining bolts. c) Ensure ail hoses are correctly reconnected and, where necessary, /her their retaining clips are securely tightened. d) Adjust the accelerator cable as described in Section 4.

Fuel
rail and injectors
Removal 7 Disconnect the battery negative terminal (refer to Disconnecting tho battery in the Reference Section of this manual). 6 Remove the throttle body assembly as described earlier in this Section, however it is only necessary to move the unit to one side for access to the fuel rail and therefore it Is unnecessary to disconnect the accelerator caWe and hoses etc.
9 Depressurise Ihe fuel system as described in Section 9. 10 Loosen the clips or release the quick-release couplings and disconnect the fuel inlet and, on pre-1998 models, outlet hoses from the fuel rail. Note the fitted positions of the hoses to aid refitting later. 11 Unplug the ln}ector wiring harness connectors, labelling them to aid correct refitting later. 12 Unscrew the bolts securing the fuel rail assembly to the Inlet manifold, then carefully pull the Injectors from the Inlet manifold. Remove the assembly from the engine and remove the injector lower O-ring seals. 13 The injectors can be removed Individually from the fuel rail by extracting the relevant metal clip and easing Ihe injector out of the rail. Remove the injector upper O-ring seals (see illustration).
14 On pre-1998 models, if necessary remove the retaining clip and remove the fuel pressure regulator from the fuel rail. 15 Check the electrical resistance of the injector using a multimeter and compare It with the Specifications. Note: If a faulty Injector is suspected, before condemning the injector, It is worth trying the effect of one of the proprietary injector-cleaning treatments. Refitting 16 Refit the injectors and fuel rail by following the removal procedure, in reverse, noting the following points: a) Renew the injector O-rlng seals, and smear them with a little Vaseline before assembling. Take care when fitting the injectors to the fuel rail and do not press them in further than required to fit the retaining clip otherwise the O-ring seal may be damaged.
1 Fuel rail 2 Fuel pressure regulator 3 Injectors
5.13 Fuel rail and Injector removal 4 Vacuum stub connect/on 5 Fuel inlet hose 6 Fuel return hose
7 Mounting bolts 8 Injector mounting dip 9 Injector mounting dip

4A*2 Fuel system -
single-point
petrol Injection models
b) Ensure that the injector retaining clips are securely seated c) Make sure the fuel supply and return hoses are correctly fitted as noted on removal, d) Check that all vacuum and electrical connections are remade
correcily
and securely. e) On completion check the fuel rail and injectors for fuel leaks.
Fuel pressure regulator Note: On J998 models onward, the fuel pressure regulator is an integral pad of the fuel pump and cannot be renewed separately. The following procedure applies to pre-1998 models only. Removal 17 Remove the air cleaner and inlet air ducts as described In Section 2. 18 Oepressurise the fuel system as described in Section 9. 19 Disconnect the vacuum hose from the port on the side of the regulator. 20 Extract the retaining clip and pull the pressure regulator out of Ihe fuel rail. 21 Remove the O-ring seal. Refitting 22 Refit the fuel pressure regulator by following Ihe removal procedure in reverse, noting the following points: a) Renew the O'ting seal and smear it with a little Vaseline before assembling. b) When fitting the retaining clip, use a suitable socket or metal tube (o press In the three anchorage points at Ihe same time. c) Refit the vacuum hose securely.
Idle control stepper motor
23 Refer to Chapter 4A.
Throttle potentiometer 24 Refer to Chapter 4A,
Intake air temperature sensor 25 Refer to Chapter 4A.
Manifold absolute pressure (MAP) sensor 26 Reler to Chapter 4A.
6.12a Disconnect the wiring connectors for the fuel injector harness ...
6.3 Disconnect the wiring connectors from the throttle potentiometer and the idle control stepper motor
Coolant temperature sensor 27 Refer to Chapter 4A. Crankshaft TDC sensor 28 Refer to Chapter 4A. Electronic control unit (ECU)
29 Refer to Chopter 4A.
Inertia safety switch 30 Refer to Chapter 4A. Fuel injection system relays 31 Refer to Chapter 4A.
6 Engine management system ^ components
(1242
cc,16-vatve S engines) - removal and refitting ^
Note: Refer to the warning given in Section t before proceeding.
Throttle body assembly
Removal 1 Remove the resonator, air cleaner and inlet air duct as described in Section 2. 2 Free Ihe accelerator inner cab 6.12b ... and intake air temperature/pressure sensor
4 Slacken and remove the three bob j securing the throttle body assembly to ite inlet manifold. Ihen remove the assent?/ along with its insulating spacer. As the
throaii 1-
body is withdrawn, disconnect the vacuum hose from the underside of the unit. Refitting 5 Refitting is a reversal of the removal pi>: cedure, bearing in mind the following pants a) Examine the insulating spacer for signs d damage, and renew if necessary. b) Ensure the throttle body, inlet
manddd
and insulating spacer mating surfaces at -clean and dry. then fit the throttle
btxty
and spacer, and securely tighten the retaining bolts. c) Adjust Ute accelerator cable as desciter /nSecfw?4.
Fuel rail and injectors
Removal 6 Disconnect the battery negative termrul; (refer to Disconnecting the battery in ir*J Reference Section ol this manual), 7 Remove the resonator, air cleaner arid io«l 1 air duct as descnbed in Section 2. 8 Free the accelerator Inner cablc from l>*
1
throttle cam, remove the outer cable sprig. clip, then pull the outer cable out from
>H
mounting bracket rubber grommet, 9 From the side of the throttle bod/, | disconnect the wiring connectors from Ihs: throttle potentiometer and the idle cofttro^ stepper motor. 10 Oepressunse the fuel system si ' described in Section 9. ' 11 Loosen the clips or release tho quick-. release couplings and disconnect the fuel MdJ' and outlet hoses from the left-hand end oftfu fuel rail, below the throttle body. Note IM fitted positions ol the hoses to aid relirtirf i later. Undo the support bracket retaining bol and move the fuel hoses to one side. 12 Disconnect Ihe wiring connectors forth* fuel injector harness and the Intake an temperature/pressure sensor (m illustrations). 13 Disconnect the fuel pressure regulator-! vacuum hose and the EVAP purgo vaive h«* (see illustrations).
6.13a Disconnect the fuel pressure regulator vacuum hose...

4A*2 Fuel system -
single-point
petrol Injection models
6.13b ... and tho EVAP purge valve hose
14 Undo the two bolls securing the plastic nlet manifold upper section to the lower section. Release the spark plug HT lead from Ihe location groove in the manifold upper section, then lift the upper section, complete with throttle body, off the engine (see illustrations). Recover the O-nngs from the manifold ports. 16 Unscrew the two bolts securing the fuel rail assembly to the Inlet manifold lower section, inen carefully pull the injectors from ttie inlet manifold (see Illustration). Remove
tt>e
assembly from the engine and remove the injector lower O-ring seals. t& The injectors can be removed individually from the fuel rail by disconnecting the wiring connector, extracting the relevant metal clip
ano
easing the injector out of the rail. Remove themjector upper O-ring seals. 17 Check the electrical resistance of the tractor using a multimeter and compare it with the Specifications. Note: If a faulty Rector fc suspected, before condemning Wie
Rector,
it is worth trying the effect of one of m
proprietary
injector-cleaning treatments. Refitting
15 Refit the injectors and fuel rail by following tie removal procedure, In reverse, noting the Mowing points:
4} Re/few
the Injector O-ring seals, and
smear
them with a little Vaseline before assembling. Take care when fitting the
injectors
to the fuel rail and do not press
them
in further than required to fit the
retaining
clip otherwise the O-ring
seal may
be damaged.
6.14a Undo the inlet manifold upper section retaining bolts ... b) Ensure that the injector retaining clips are securely seated. c) Renew the sealing O-nngs fitted between the manifold upper and lower sections if in any doubt about their condition. d) Make sure the fuel supply and return hoses are correctly fitted as noted on removal. e) Check that all vacuum and electrical connections are remade correctly and securely. f) On completion check the fuel rail and injectors tor fuel leaks.
Fuel pressure regulator
Removal 19 Remove the resonator, air cleaner and inlet air ducts as described In Section 2. 20 Depressurise the fuel system as described In Section 9. 21 Disconnect the vacuum hose from the port on the side of the regulator. 22 Extract the retaining clip and pull the pressure regulator out of the fuel rail. 23 Remove the O-ring seal. Refitting 24 Refit the fuel pressure regulator by following the removal procedure in reverse, noting the following points: a) Renew the O-ring
seaJ
and smear it with a little Vaseline before assembling. b) When fitting the retaining clip, use a suitable socket or metal tube to press in the three anchorage points at the same time. c) Refit the vacuum hose securely.
Idle control stepper motor 25 The idle control stepper motor is an Integral part of the throttle body and cannot be individually renewed.
Throttle potentiometer 26 The throttle potentiometer Is an integral part of the throttle body and cannot be individually renewed.
Intake air temperature/pressure sensor
Removal
6.14b ... and lift off the manifold upper section and throttle body 28 Disconnect the sensor wiring connector, located on the right-hand side of the Inlet manifold upper section. 29 Undo the two screws and remove the sensor from the manifold. Refitting 30 Refitting is a reversal of the removal procedure. Coolant temperature sensor 31 Refer to Chapter 4A.
Crankshaft TDC sensor 32 Refer to Chapter 4A.
Electronic control unit (ECU)
Removal Note: 77?e engine management system has a learning capability which allows the ECU to store details of the engine's running characteristics in Its memory. This memory will be erased by the disconnection of the battery cables, with the result that the engine may idle roughly, or lack performance for a while, until the engine's characteristics are re-learnt. 33 The ECU (electronic control unit) is located on the right-hand inner wing panel. 34 Disconnect the battery negative terminal (refer to Disconnecting the battery In the Reference Section of this manual). 35 Undo the mounting bracket nuts and withdraw the unit from the inner wing (see Illustration). 36 Disconnect the ECU wiring connector, then remove the unit from the engine compartment.
6.15 Fuel rail securing bolts (arrowed) 27 Remove the resonator, air cleaner and inlet air duct as described in Section 2. 6.35 Undo the mounting bracket nuts and withdraw the ECU from the inner wing

Fuel system - diesel models 4C*3
bolt (Bosch)
4 Fuel system -priming and bleeding
The Injection pump Is self-priming and no special procedures are necessary to prime the fuel system. However where the luei system has been completely drained it (s helpful to loosen the injector union nuts while turning the engine on the starter motor In order to purge trooped air.
S Fuel injection pump • removal and refitting 5
Removal 1 Disconnect the battery negative terminal (refer to Disconnecting the battery In the Reference Section of this manual) 2 Remove the timing belt and Injection pump sprocket aa described in Chapter 2C. 3 Disconnect the accelerator cable from the fuel injection pump, with reference to Section 3. 4 Loosen the clip, or undo the banjo union, and disconnect the fuel supply hose. Recover the sealing washers from the banjo union, where applicable. Cover the open end of the hose, and raflt and cover the banjo bolt to keep dirt out. 5 Disconnect the main fuel return pipe and the injector leak-off return pipe banjo union. Recover the sealing washers from the banjo union Again, cover the open end of the hose and the banjo bolt to keep dirt out.
6.2a Remove the rubber bung ...
k
5.10a Injection pump lower mounting bolt removal (Bosch) 6 Disconnect all relevant wiring from the pump. 7 Unscrew the union nuts securing the Injector pipes to the fuel Injection pump and injectors. Counterhold the unions on Ihe pump, while unscrewing the pipe-to-pump union nuts. Remove the pipes as a set. Cover open unions lo keep dirt out. using small plastic begs, or fingers cut from discarded (but clean!) rubber gloves. 8 Mark the fuel Injection pump in relation to the mounting bracket, using a scriber or felt tip pen. This will ensure Ihe correct pump timing is retained when refitting. 9 Unscrew the bolt(s) from Ihe rear support bracket (see illustration) 10 Unscrew the mounting nuts/bolt, remove the special bracket, then remove the injection pump from the mounting bracket/housing (see illustrations).
Refitting 11 Locate the injection pump In the mounting bracket and align the marks mode on the pump and bracket before removal. If a new pump is being fitted, transfer the mark from the old pump to give an approximate setting. Locate the special bracket and fit the nuts/bolt loosely. 12 Refil Ihe rear support bracket and fit the bolts loosely. 13 Set up the injection timing, as described In Sections 7 and 8 (as applicable). 14 Refil and reconnect the injector fuel pipes. 15 Reconnect all relevant wiring to the pump. 16 Reconnect the fuel supply and return hoses, and tighten the unions, as applicable.
6.2b ... when checking the injection pump timing dynamically. Timing marks shown on flywheel and transmission casing
5.10b Removing the special Injection pump mounting brackot (Bosch)
5.10c Removing tho injection pump (Bosch) Use new sealing washers on the banjo unions. 17 Reconnect and adjust the accelerator . cable with reference to Section 3. i 16 Refit the Injection pump sprocket end timing belt as described in Chapter 2C. I 19 Reconnect Ihe battery negative terminal 20 Start the engine, and check for any ' leakage at the fuel unions. To enable the engine to start It may be necessary to loos® the injector union nuts while turning the engine on the starter motor in order to porgt trapped air. 21 Check and if necessary adjust the idle speed as described in Chapter 1B.
6 injection timing -checking methods
1 Checking the injection timing Is not e routlno operation. It Is only necessary aftorth* Injection pump has been disturbed. I 2 Dynamic timing equipment does exist, bulit ' is unlikely to be available to the hame I mechanic. Tho equipment works by I converting pressure pulses in an Injector pips into electrical signals. If such equipment« available, use it In accordance with Its maker's instructions using the liming mark
on
the flywheel (see illustrations). 3 Static timing as described In this Chaptai gives good results If carried out carefully. A dial test indicator will be needed, with probes and adapters appropriate to the typo of infection pump. Read through the procedures beto starting work, to find out what ts Involved.

4D*2 Exhaust and emission control systems
2.2 Charcoal canister location behind tho right-hand headlight
conditions, via a plunger valve, The system is controlled electronically by means of an emissions system control unit. Evaporative emission control • petrol models To minimise the escape of unburned hydrocarbons Into the atmosphere, an evaporallve loss emission control system is fitted to petrol models, The fuel tank filler cap Is sealed and a charcoal canister is mounted underneath the right-hand headlamp to collect the petrol vapours released from the fuel contained In the fuel tank. It stores them until they can be drawn from the canister (under the control of the fuel Injection/ignition system ECU) via the purge valve into the Inlet tract, where they are then burned by the engine during normal combustion. To ensure thai the engine runs correctly when it is cold and/or idling and to protect the catalytic converter from the effects of an over-rich mixture, the purge control valve is not opened by the ECU until the engine has warmed up, and the engine is under load; the valve solenoid is then modulated on and off to allow the stored vapour to pass into the inlet tract.
Exhaust systems The exhaust system comprises the exhaust manifold, an exhaust downpipe, • catalytic convorter, an intermediate pipe with silencer, and a tailpipe with silencer, On turbo diesel models the turbocharger is fitted between ihe exhaust manifold and the downpipe.
5.5a On 16-valve engines, undo the bolts and remove the manifold heat shield...
2 Evaporative loss emission ^ control system - information and component renewal ^
Information 1 The evaporative loss omission control system consists of the control solenoid (or purge valve), the activated charcoal filter canister and a series of connecting vacuum hoses. 2 The control solenoid and charcoal canister are both mounted on the right-hand side of the engine compartment behind the headlight (see illustration).
Component renewal
Control solenoid 3 With the bonnet open, disconnect the hoses from the control solenoid on the top of the charcoal canister. 4 Disconnect the wiring and remove the solenoid. 5 Refitting is a reversal of removal. Charcoal canister 6 Remove Ihe control solenoid as desenbed previously. 7 Disconnect Ihe fuel tonk hose from the canister 8 Detach the mounting and remove the canister. 9 Refitting Is a reversal of removal. Multifunction valve 10 The multifunction valve >s mounted on top of the luel tank. Removal and refitting is similar to that described for the tank sender gauge/pump (refer to Chapter 4A or 4B).
3 Crankcase emission system - general information
The crankcase emission control system consists of a hose from the camshaft cover to the air cloanor with a branch to Ihe throttle body. The main hose Incorporates a flame trap and the Inlet to the throttle body incorporates a calibrated hole.
5.5b ... then remove the bracket
The system requires no attention other than to check at regular intervals that tho hoses are free of blockages and undamaged.
4 Lambda oxygen sensor -removal and refitting &
Note: 7?5e Lambda oxygen sensor is doiicata and will not work if it is dropped or knocked, it its power supply is disrupted, or if any cleaning materials are used on it.
Removal 1 The sensor Is threaded Into the exhaust front downpipe. Access if best gained Irom underneath the vehicle. Apply the handbrake then )ack up the front of the vehicle and support on axle stands (see Jacking and vehicle support). 2 Disconnect the sensor wiring connector located on the front of the engine. 3 Working beneath the vehicle, unscrew the sensor, taking care to avoid damaging the sensor probe as it Is removed- Note: As a flying lead remains connected to the sensor after it has been disconnected, if the correct spanner is not available, a slotted socket
will
be required to remove the sensor.
Refitting A Apply a little anti-selze grease to (he sensor threads • avoid contaminating the probe tip. 5 Refit the sensor to the downpipe. tightening it to the correct torque. Reconnect the wiring. 6 Lower the vohicle to the ground.
5 Exhaust manifold - % removal and refitting jk
Petrol models
Removal 1 On 1242 cc (16-valve) engines, remove tho air cleaner and inlet system components as described in Chapter 48. 2 Firmly apply the handbrake, then jock up the front of the car and support It securely on axle stands (see Jacking and vehicle support). 3 Disconnect the oxygen sensor wiring or alternatively romovo Ihe sensor completely. 4 Unscrew the nuts and disconnect the exhaust downpipo from Ihe exhaust manifold flange. Recover the gasket. 5 On 1242 cc (16-valve) engines, undo the bolts and remove the manifold heat shield, then remove the bracket at the timing belt end of the manifold (seo Illustrations). 6 Unscrew the mounting nuts, remove the washers, and recover any additional brackets fitted over the studs, noting their locations. Withdraw the manifold from the studs on the cylinder head. 7 Recover the gaskets from Ihe studs.