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Marea- Marea Weekend & Engine
2000 range (§) Fuel feed system
ENGINE MANAGEMENT SYSTEM
Foreword
The Marea-Marea Weekend 1998 20v is equipped with a 5 cylinder in line engine with 20 valves, 1998
cc, twin overhead camshaft and a Bosch ME3.1 integrated electronic injection/ignition system.
The fuel system differs from the one described for the 1998 20v "99 range" version through the addition
of several variants to make it compatible with the EEC Stage 3 EOBD regulations.
The main modifications to the system can be summarized as follows:
- Catalytic converter near the exhaust manifold to take maximum advantage of the heat of the gases.
- Two Lambda sensors, one upstream (front) and one downstream (rear) which check the quality of the
exhaust gases and the operation of the catalyzer.
- Adoption of an accelerometre sensor on the right shock absorber turret, used to distinguish between
engine torque variations doe to the uneveness of the road surface and those due to failed ignition in
the combustion chamber (misfire).
- Adoption of a timing sensor on the inlet side timing pulley.
- Multi-purpose valve on the tank to prevent leaks.
- Adoption of raipd attachment connectors for the anti-evaporation system pipes.
- Cap on the fuel filler with an attachment cable.
For further information on the fuel system, refer to publication 507137.
DIAGRAM SHOWING ENGINE EXHAUST ASSEMBLY
4F001WJ01
Key
1. Exhaust manifold
2. Catalytic converter
3. Front Lambda sensor
4. Rear Lambda sensor
5. Silencers
Copyright by Fiat Auto 1
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Engine
Fuel feed system
Marea-Marea Weekend ®> *»
2000 range @)
10.
LOCATION OF INJECTION/IGNITION SYSTEM COMPONENTS
Key
1. Variable valve timing control solenoid
2. Injectors
3. Fuel vapour cut-out solenoid valve
4. Injection/ignition control unit
5. General system protective fuse
6. Flow meter/air temperature sensor
7. Motorized throttle body
8. Engine coolant temperature sensor
9. Vehicle speed sensor
10. Variable geometry manifold actuator solenoid
valve
11. RPM sensor
12. Front Lambda sensor connector
13. Ignition coil
14. Timing sensor
15. Rear Lambda sensor connector
16. Detonation sensors
17. Accelerometer
LOCATION OF DIAGNOSTIC SOCKET
The diagnostic socket for the analysis of the en
gine management system is located under the
junction unit in the dashboard. This socket also
makes a connection with the diagnostic equip
ment (Examiner or other instruments) for the
other electronic control units on the vehicle.
It is a "standardized" 16-way diagnostic socket
which can be connected to the diagnostic equip
ment using the "MPX97" adaptor.
2 Print n° 506.763/23
Page 80 of 330
Marea- Marea Weekend •
2000 range ©
Engine
Fuel feed system
10.
REMOVING-REFITTING ACCELEROMETER
Removing
- Disconnect the negative battery terminal.
1. Disconnect the electrical connector (1a),
undo the fixing bolts (1b) and remove the
device (1c).
Refitting
- Reverse the order of the operations carried
out for the removal.
REMOVING-REFITTING FRONT LAMBDA
SENSOR
Removing
- Position the vehicle on a lift.
- Disconnect the negative battery terminal.
- Raise the lift.
2. Undo the lower fixing bolts (1a) and the
side fixing bolts (1b) and remove the
shield (1c) under the engine.
3. Undo the fixing nuts (1a) and remove the
lower section (1 b) of the heat shield.
4. Disconnect the electrical connector (1a)
and undo the front Lambda sensor (1b).
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Engine
Fuel feed system
Marea- Marea Weekend 9
2000 range ©
- Release the electrical wiring for the front
Lambda sensor from the retaining bands
and remove the sensor.
Refitting
NOTE Apply special grease (e.g. Bosch VS
14016- FT) to the threaded part ot
the sensor
- Place the Lambda sensor in position and
tighten to torque.
E Lambda sensor : 4.5 daNm
Reverse the order of the operations de
scribed for the removal.
REMOVING-REFITTING REAR LAMBDA
SENSOR
Removing
- Position the vehicle on a lift.
- Disconnect the negative battery terminal.
1. Disconnect the electrical connector (1a)
and release the electrical wiring from the
retaining bands.
- Raise the lift.
2. Undo the lower fixing bolts (1a) and the
side fixing bolts (1b) and remove the
shield (1c) under the engine.
3. Use tool USAG 875 (1a), shown in the
diagram or a similar tool to undo the rear
Lambda sensor.
Refitting
NOTE Apply special grease (e.g. Bosch VS
14016- FT) to the threaded part of
the sensor.
- Place the Lambda sensor in position and
tighten to torque.
E Lambda sensor: 4.5 daNm
Reverse the order of the operations carried
out for the removal.
4 Print n° 506.763/23
Page 84 of 330
Marea- Marea Weekend 9
2000 range ©
Engine
Fuel feed system
10.
REMOVING-REFITTING CATALYTIC
CONVERTER
Removing
- Position the vehicle on a lift.
- Disconnect the negative battery terminal.
- Remove: the upper and lower heat shields,
the front and rear Lambda sensors, carrying
out the operations described in the relevant
chapters.
- Lower the lift.
1. Undo the fixing nuts (1a) and separate the
catalytic converter (1b) from the exhaust
manifold (1c).
E
Nuts la: 3.2 daNm
- Raise the lift.
2. Undo the fixing nuts (1a) and separate the
exhaust pipe (1 b).
EI
Nuts 1a: 4.2 daNm
3. Undo the nuts (1a) and the bolts (1b) and
remove the bracket (1c).
E
E
Nuts 1a: 2.5 daNm
Bolts 1b: 2.5 daNm
- Remove the catalytic converter.
Refitting
- Reverse the order of the operations carried
out for the removal.
Copyright by Fiat Auto 7
Page 139 of 330
Marea-Marea Weekend Electrical equipment
2000 range (§) Location of components on the car
55.
LOCATION OF RELAYS AND FUSES ON THE VEHICLE (BONNET - Petrol engine types)
Fi998l152B 273 274 i * *
3B-3C Power fusebox
96 Power fuse protecting ABS
98 Headlamp washer intermittent function
122 Engine cooling fan low speed relay
123 Engine cooling fan high speed timer
124 Air condiitoning compressor control relay
129 Power fuse protecting engine coling fan
150 Injection system relay feed
151 Lambda probe control relay for fuel pump
and injectors
152 Fuse protecting injection system
152A Fuse protecting injection system
152B Fuse protecting injection system
273 Fuse protecting automatic transmission
system
274 Fuse protecting automatic transmission
system
276 Starter enablement relay
(••) Versions with air conditioning
(*) With automatic transmission
Copyright by Fiat Auto 9
Page 141 of 330
Marea-Marea Weekend Electrical equipment
2000 range (§) Location of components on the car
55.
LOCATION OF RELAYS AND FUSES ON THE CAR (PASSENGER COMPARTMENT)
3A/D Supplementary fusebox 332 Ignition activated power relay.
4 Junction unit 344 I.E. protective fuse
5 Dipped headlamps relay feed
32 Fog lamp control relay
150 Injection system relay feed
151 Lambda probe control relay for fuel pump
and injectors
152 Fuse protecting injection system
326 Additional heater control unit
328 Hazard warning lights relay
Copyright by Fiat Auto 11
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Electrical equipment
Component location
Marea-Marea Weekend
2000 range ©
55.
Starting - Electronic ignition and injection - Recharging and warning light
light - Injection system failure warning light - Rev counter (1596)
Insufficient engine oil pressure warning
Component key
3 Power fusebox
4 Junction unit:
6 Instrument panel
8 Left front earth
10 Engine battery earth
12 Ignition switch
18 Left rear earth
2 Left facia earth
55 Front/engine lead connection
56 Fuel level gauge control unit
57 Inertia switch
70 Connection between dashborad/front
cables
132 Petrol vapour cut out solenoid valve
136 Knock sensor
138 Idle adjustment actuator
141A Heated Lambda sensor (upstream of
cat.)
141 B Heated Lambda sensor (downstream of
cat.)
143 Alternator
144 Rpm and TDC sensor
145 Starter motor
146 Potentiometer on throttle valve
150 Injection system relay feed
152 Fuse protecting injection system
155 Ignition coil unit
156 Spark plugs
162 Injector (1st)
163 Injector (2nd)
164 Injector (3rd)
165 Injector (4th)
168 Timing sensor
193 Earth for electronic injection
194 Injection lead/injector braid connection
195 Ignition/ injection control unit (1596)
334 Dual engine temperature sender unit
373 Air pressure and temperature sensor
375 Standardized diagnostic socket
55 Front/engine lead connection
1596
CN6A.
HG6A.
* HN 6A
1 CN n.d.
MB6A.
NZ8_
* ZB n.d
*RG195A_
HM6A
CN n.d. HN 143 *
HG 142
1 95A Injection/ignition electronic control unit (1596)
1596 1 N 141A* 20 L 141A* 29 RN n.d. *
2 NZ141B* 21 BN 127 35 B 127
4 L6A* 23 GN 6A* 36 LR252 [c*
5 V252 0 23 GN70 0 40 AG 127
9 LN 141A* 24 B141B* 41 MG 127
12 R 141B* 25 BR n.d. 0 44 Vn.d.*
13 GV131 25 BR 375 * 46 BG 268 [a
14 AB 127 26 LN6A* 47 C n.d. *
15 SB 150* 27 N 193* 48 S 127
16 GN 252 [cal 28 N 193* 49 NZ252
27 282,9 41 52
O I I I I I I -r-r-r'n , , r'l -r-
rrrri '/ 1 1 1 1 1 1 1 1 1 1 1 \1 L/-HJ 'A i I I i i ,I
40
1 95B Injection/ignition electronic control unit (1596)
1596 53 R144* 65 VB 138* JL. NZn.d. *
54 N n.d. * 66 LR 155 * _ZL HM194*
55 ZB 278 * 67 B 144* _7JL HV194*
56 L136* 68 V278*
57 C138* 69 B 168*
58 HN 138* 70 Z136*
59 GN 155 * 71 HG 194 *
60 S 146* 72 HL194*
62 SN 339 * 75 RN 278 *
64 GR138* 76 BR 146 *
74
67-Jf Mill i i r r-l I I I
60-
IE
L -j |l
53 59
The cables involved in the wiring diagram are marked with an asterisk.
70 Print n° 506.763/23