1988 OPEL CALIBRA turn signal

Wiring diagrams 12•55
12
Key to wiring diagrams for 1992 and later models
NoDescriptionTrackNoDescriptionTrack
E1Left parking lamp506
E2Left tail lamp507, 745
E3Licence plate lamp513
E4Right parking lamp509
E5Right tail lamp510, 746
E6Engine compartment lamp515
E7Left high beam 535
E8Right high beam536
E9Left low beam537, 747
E10Right low beam538, 748
E11Instrument lights728, 729
E12Selector lever lamp 498, 499
E13Boot lamp585
E14Passenger compartment lamp587
E15Glove box lamp677
E16Cigarette lighter lamp676
E17Left reversing lamp597
E18Right reversing lamp598
E19Heated back window652
E20Left fog lamp553
E21Right fog lamp554
E24Left rear fog lamp548
E25Left front heating mat660
E27Left rear reading lamp680, 681
E28Right rear reading lamp683, 684
E30Right front heating mat664
E32Clock lamp863
E37Left mirror make-up lamp686
E38Computer lamp854
E39Right rear foglamp549
E40Right mirror make-up lamp688
E41Passenger compartment delay lamp 588 to 590
E50Driver door lamp866
E51Passenger door lamp884
F1 onFusesVarious
F35Voltage stabilizer702
G1Battery101
G2Alternator114
G6Diesel alternator 402 to 405
H1Radio784 to 798
H3Turn signal lamp telltale716, 718
H4Oil pressure telltale710
H5Brake fluid telltale712
H6Telltale hazard warning system570
H7Charging indicator lamp710
H8High beam telltale722
H9Left stop lamp561, 749
H10Right stop lamp562, 750
H11Left front turn signal lamp572
H12Left rear turn signal lamp573
H13Right front turn signal lamp581
H14Right rear turn signal lamp582
H15Fuel telltale705, 706
H16Preheating time telltale715
H17Trailer turn signal lamp telltale717
H18Horn670
H19Headlamps on warning buzzer594, 595
H21Parking brake telltale713
H23Airbag telltale719
H25Heated back window & mirror telltale642, 765
H26ABS telltale721
H27Safety checking warning buzzer996 to 998
H28Seat belt warning telltale723
H30Engine telltale724H33Left auxiliary turn signal lamp576
H34Right auxiliary turn signal lamp578
H36Additional stop lamp563
H37Left front loudspeaker788 to 790
H38Right front loudspeaker794 to 796
H39Left rear loudspeaker788, 789
H40Right rear loudspeaker791, 792
H42Automatic program power telltale725
H45Four wheel drive telltale727
H46Catalytic converter temperature telltale729
H47Anti-theft warning unit horn838
H48Horn671
H51Traction control telltale720
H52Left front tweeter787 to 791
H53Right front tweeter793 to 797
K3Starter relay anti-theft warning unit109, 110
K5Fog lamps relay554 to 555
K6Air conditioning relay901, 902
K7Four stage air conditioning blower relay904, 905
K8Windshield wiper interval relay603 to 606
K9Headlamps washer unit relay619, 620
K10Flasher unit567 to 569
K20Ignition coil module149, 150, 171, 172, 241, 242, 302 to 305,
361 to 364, 1001 to 1005, 1055 to 1061
K22Coolant pump relay133, 134, 969, 970
K25Glow time relay440 to 443
K26Radiator blower relays972 to 974
K27Radiator blower relay137 to 139
K30Back window wiper interval relay613 to 615
K31Airbag control unit1191 to 1198
K34Radiator blower time delay relay356 to 358, 956 to 958
K35Heated back window & mirror time delay relay650 to 652
K37Central locking control unit805 to 812
K51Radiator blower relay430, 431, 942, 943, 956, 957
K52Radiator blower relay145 to 147, 433,435,
982 to 984, 960 to 962
K57Multec unit control211 to 230, 244 to 262
K58Fuel pump relay231, 232, 262, 263
K59Running light relay520 to 525
K60Compressor relay931,932
K61Motronic control unit270 to 294, 307 to 337,
366 to 396, 1007 to 1037, 1063 to 1096
K63Horn relay671, 672
K641 stage air conditioning blower relay913, 914
K67Radiator blower relay142, 143, 436, 437, 948,
949, 964, 965, 986, 987
K68Fuel injection unit relay295 to 299, 393 to 397,
334 to 338, 1093 to 1097, 1034 to 1038
K73High beam relay (Calibra)530, 531
K76Glow time control unit413 to 417
K77Glow plugs relay419, 420
K78Preresistor relay (70A)422, 423
K79Charge indicator relay406 to 408
K80Filter heating relay426, 427, 452, 453
K82Engine revolution relay447, 448
K83Four wheel drive unit control342 to 349
K84EZ Plus control unit155 to 166, 177 to 191
K85Automatic transmission control unit473 to 496
K86Check control unit736 to 752
K87Radiator blower relay945, 946, 953, 954, 977, 978
K88Catalytic converter temperature control unit462 to 464
K89Rear fog lamp relay543 to 545
K90Compressor relay (automatic transmission only)930, 931
K94Anti-theft warning unit control unit833 to 847

12•56Wiring diagrams
Key to wiring diagrams for 1992 and later models (continued)
NoDescriptionTrackNoDescriptionTrack
K95Traction control control unit1125 to 1140
K97Headlamps washer pump time delay relay630 to 632
K101Parking position mirror relay774 to 777
K102Park brake shift lock control unit 469 to 471
L1Ignition coil150, 172, 205, 273, 241, 302, 361
L2Ignition coil1000 to 1004, 1054 to 1059
M1Starter105, 106
M2Windshield wiper motor601 to 604
M3Heating blower motor127 to 129
M4Radiator blower motor118, 120, 140, 356, 431, 948, 954, 980
M6Left headlamp wiper motor622 to 624
M7Right headlamp wiper motor 626 to 628
M8Back window wiper motor611 to 613
M10Air conditioning blower motor905 to 908
M11Radiator blower motor136, 434, 962, 984
M13Vectra/Cavalier sun roof motor1172 to 1175
M13.1Sun roof motor1172, 1174
M13.2Timing box microswitch1172
M13.3Timing box microswitch1174
M18Driver door central locking motor807 to 810
M19Left rear door central locking motor821 to 823
M20Right rear door central locking motor825 to 827
M21Fuel pump232, 263, 297, 339, 399, 834, 1098, 1039
M23Alternator blower motor135, 974
M24Headlamps washer pump632
M26Automatic antenna motor798 to 799
M30Driver side outside mirror638 to 641
M31Passenger side outside mirror644 to 647
M32Passenger door central locking motor813 to 816
M33Idle speed actuator285, 286, 317, 318, 381,
382, 1019, 1020, 1075, 1076
M37Tail gate/boot lid central locking motor818 to 821
M39Left headlamp levelling motor 692 to 695
M40Right headlamp levelling motor696 to 699
M41Fuel filler door central locking motor823, 824
M47Driver door window lifter motor867 to 871
M48Passenger door window lifter motor885 to 889
M49Left rear window lifter motor873 to 877
M50Right rear window lifter motor891 to 895
M55Windshield and back window washer pump617
M57Coolant pump134, 970
M60Calibra tailgate central locking motor827, 828
M61Calibra sun roof motor1178 to 1186
M61.1Sun roof motor1179 to 1182
M61.2Relay 11178, 1179
M61.3Relay 21184 to 1186
M62Driver side outside mirror760 to 767
M63Passenger side outside mirror769 to 776
M65TC throttle valve actuator1130 to 1134
M66Idle air stepper motor215 to 218, 250 to 253
P1Fuel indicator704
P2Coolant temperature indicator706
P3Clock862
P4Fuel sensor704
P5Coolant temperature sensor706
P7Tachometer708
P11Airflow meter 285 to 289
P12Coolant temperature sensor282, 381
P13Outside temperature sensor856
P14Distance sensor412, 413
P17Left front revolution sensor1110, 1154
P18Right front revolution sensor1113, 1157
P19Left rear revolution sensor1116, 1160
P20Right rear revolution sensor1119, 1163P21Distance sensor731
P23Intake manifold absolute pressure sensor160, 161, 185, 186,
217 to 219, 250 to 252
P24Engine oil temperature sensor162, 187
P27Left front brake lining sensor740
P28Right front brake lining sensor740
P29Intake manifold temperature sensor382, 1016, 1072
P30Coolant temperature sensor215, 248, 313, 1017, 1073
P32Heated exhaust oxygen sensor294, 295, 331, 332, 391,
392, 1034, 1035, 1093, 1094
P33Exhaust oxygen sensor229, 257
P34Throttle valve potentiometer221 to 223, 280, 281, 253 to 255,
383 to 385, 478, 479, 1018, 1019, 1074, 1075
P35Crankshaft impulse sensor178 to 180, 289 to 291, 248 to 250,
318 to 320, 373 to 375, 1025 to 1027, 1084 to 1086
P38Transmission oil temperature sensor494
P39Trailer bulb test sensor752 to 754
P43Electronic speedometer733
P44Air mass meter393 to 397, 334 to 338,
1037, 1038, 1096, 1097
P45Transmission input revolution sensor490, 491
P46Knock control sensor322, 323, 377, 378,
1022, 1023, 1078, 1079
P47Cylinder identification hall sensor325 to 327, 385 to 387,
1028 to 1030, 1087, 1089
P48Automatic transmission distance sensor488, 489
P50Catalytic converter temperature sensor463, 464
P53Driver side anti-theft warning unit sensor839 to 847
P54Passenger side anti-theft warning unit sensor839 to 847
P55Engine coolant temperature sensor415
P56Knock control sensor II1080, 1081
P57Antenna797
R3Cigarette lighter675
R5Glow plugs418 to 420, 441 to 443
R13Left heated washer nozzle 626
R14Right heated washer nozzle628
R19Radiator blower preresistor120, 140, 945
R22Glow plugs pre-resistor423
R23Driver airbag squib1194
S1Starter switch103 to 106
S1.2Key contact switch783
S2Light switch assy
S2.1Light switch504 to 507
S2.2Passenger compartment lamp switch587
S2.3Instrument lights dimmer728
S3Heating blower switch123 to 130
S4Heated back window & mirror switch654 to 657
S5Turn signal switch assy
S5.2Low beam switch536, 537
S5.3Turn signal switch580 to 582
S5.4Parking lamp switch501, 502
S7Back up lamp switch597, 599
S8Stop lamp switch562
S9Wiper unit switch
S9.2Interval windshield wiper switch601 to 604
S9.5Back window and washer unit wiper switch614 to 616
S10Automatic transmission switch472 to 478
S11Brake fluid control switch712
S13Parking brake switch713
S14Oil pressure switch710
S15Boot lamp switch585
S17Passenger door contact switch590
S20Pressure switch
S20.1Low pressure compressor switch925

28The system also incorporates a separate
ignition amplifier module that transmits
amplified signals from the main system
module to trigger the HT pulse from the
ignition coil. The module is mounted on the
ignition coil’s bracket/baseplate.
29Additionally, the Motronic module
receives information from a cylinder
block-mounted knock sensor, which senses
“knocking” (or pre-ignition) just as it begins to
occur, enabling the module to retard the
ignition timing, thus preventing engine
damage.
Simtec 56.1
30This system uses increased amount of
electronic components instead of mechanical
parts as sensors and actuators with the
Simtec engine management system. This
provides more precise operating data as well
as greater problem free motoring.
31The control unit is equipped with
electronic ignition control. Called ‘Micropro-
cessor Spark Timing System, inductive
triggered’, (or MSTS-i), and means that the
mechanical high voltage distributor is no
longer needed. It is located behind the trim
panel, on the right-hand side footwell (door
pillar).
32The ignition coil is replaced by a dual
spark ignition coil, which is switched directly
by the output stages in the control unit.
33A camshaft sensor will maintain
emergency operation, should the crankshaft
inductive pulse pick-up, malfunction. These
sense TDC (‘Top Dead Centre’), crankshaft
angle and engine speed. The signals are used
by the control unit to calculate ignition point
and for fuel injection.
34The ‘hot film airflow meter’ determines the
mass of air taken in by the engine. The system
uses this information to calculate the correct
amount of fuel needed for injection in the
engine.
35The air inlet temperature sensor (NTC), is
fitted in the air inlet duct between the air
cleaner and the hot mass air flow meter.
36A controlled canister purge valve is
actuated by the system. The tank ventilation is
monitored closely with the Lambda control (or
oxygen sensor) and adaptation by the
computer within the control unit.
37A knock control system is also fitted. This
eliminates the need for octane number
adjustment, as it is performed automatically
through the control unit.
3Electrical system -
precautions
1It is necessary to take extra care when
working on the electrical system, to avoid
damage to semi-conductor devices (diodes
and transistors), and to avoid the risk of
personal injury. Along with the precautions
given in the “Safety first!” Section at the
beginning of this manual, take note of the
following points when working on the system.
2Always remove rings, watches, etc. before
working on the electrical system. Even with
the battery disconnected, discharge could
occur if a component live terminal is earthed
through a metal object. This could cause a
shock or nasty burn.
3Do not reverse the battery connections.
Components such as the alternator, or any
other component having semi-conductor
circuitry, could be irreparably damaged.
4If the engine is being started using jump
leads and a slave battery, connect the
batteries positive to positive and negative to
negative. This also applies when connecting a
battery charger.
5Never disconnect the battery terminals, or
alternator multi-plug connector, when the
engine is running.
6The battery leads and alternator wiring
must be disconnected before carrying out any
electric welding on the vehicle.
7Never use an ohmmeter of the type
incorporating a hand-cranked generator for
circuit or continuity testing.
8Engine management modules are very
sensitive components, and certain
precautions must be taken, to avoid damage
to the module when working on a vehicle
equipped with an engine management
system, as follows.
9When carrying out welding operations on
the vehicle using electric welding equipment,
the battery and alternator should be
disconnected.
10Although underbonnet-mounted modules
will tolerate normal underbonnet conditions,
they can be adversely affected by excess heat
or moisture. If using welding equipment or
pressure washing equipment near the
module, take care not to direct heat, or jets of
water or steam, at the module. If this cannot
be avoided, remove the module from the
vehicle, and protect its wiring plug with a
plastic bag.
11Before disconnecting any wiring, or
removing components, always ensure that the
ignition is switched off.
12Do not attempt to improvise fault
diagnosis procedures using a test lamp or
multimeter, as irreparable damage could be
caused to the module.13After working on ignition/engine
management system components, ensure
that all wiring is correctly reconnected before
reconnecting the battery or switching on the
ignition.
14Any ignition system that uses a
“Hall-effect” generator in the distributor,
cannot be tested. Test equipment that uses
its own power source (e.g. an ohmmeter),
when connected to the distributor or the
“Hall-effect” generator, will be damaged.
4Ignition system testing -
general
3
Note: Refer to Section 3 before proceeding.
Always switch off the ignition before
disconnecting or connecting any component
and when using a multi-meter to check
resistances. Any voltmeter or multi-meter
used to test ignition system components must
have an impedance of 10 meg ohms or
greater
1Electronic ignition system components are
normally very reliable. Most faults are far more
likely to be due to loose or dirty connections,
or to “tracking” of HT voltage due to dirt,
dampness or damaged insulation than to
component failure. Always check all wiring
thoroughly before condemning an electrical
component and work methodically to
eliminate all other possibilities before deciding
that a particular component is faulty.
2The old practice of checking for a spark by
holding the live end of a HT lead a short
distance away from the engine is not
recommended. Not only is there a high risk of
a powerful electric shock, but the ignition coil
or amplifier module will be damaged.
Similarly, never try to “diagnose” misfires by
pulling off one HT lead at a time. Note also
that the ECU is at risk if the system is
triggered with an open (i.e., not properly
earthed) HT circuit; ECU’s are very expensive
to replace, so take care!
3If you are in any doubt as to your skill and
ability to test an ignition system component or
if you do not have the required equipment,
take the vehicle to a suitably equipped
Vauxhall dealer. It is better to pay the labour
charges involved in having the vehicle
checked by an expert than to risk damage to
the system or to yourself.
4If the engine either will not turn over at all,
or only turns very slowly, check the battery
and starter motor. Connect a voltmeter across
the battery terminals (meter positive probe to
battery positive terminal) and disconnect the
ignition coil HT lead from the distributor cap
and earth. Note the voltage reading obtained
while turning over the engine on the starter for
(no more than) ten seconds. If the reading
obtained is less than approximately 9.5 volts,
check the battery, battery connections, starter
motor and charging system.
5•4Engine electrical systems
Warning: The HT voltage
generated by an electronic
ignition system is extremely
high and, in certain
circumstances, could prove fatal. Take
care to avoid receiving electric shocks
from the HT side of the ignition system.
Do not handle HT leads, or touch the
distributor or coil, when the engine is
running. If tracing faults in the HT circuit,
use well-insulated tools to manipulate live
leads

Inspection
17Examine the distributor cap and rotor arm,
as described in paragraphs 6 and 7. Examine
the O-rings at the rear of the distributor body,
and on the rear of the shaft, and renew if
necessary.
Reassembly
18Reassembly is a reversal of dismantling,
ensuring that the thrustwashers are correctly
located. Note that the drive collar should be
refitted so that the drive peg on the collar is
aligned with the groove in the top of the
distributor shaft (it is possible to fit the drive
collar 180°out of position).
19Refit the distributor as described in
Section 18, and then check and if necessary
adjust the ignition timing, as described in
Section 21.
DOHC models (where
applicable)
20The distributor cap and rotor arm can be
examined as described in paragraphs 6 and 7.
21Ignition timing -checking and
adjustment
4
Note: Refer to Section 3 before proceeding. A
tachometer and a timing light will be required
during this procedure. For details of ignition
timing adjustment required to operate vehicles
on unleaded petrol, refer to Section 22.
14 NV and 16 SV models
Checking
1Start the engine and run it until it reaches
normal operating temperature, then switch
off.
2On 14 NV models, disconnect the vacuum
pipe from the distributor vacuum diaphragm
unit.
3On all models use a spanner applied to the
crankshaft pulley bolt to rotate the crankshaft
clockwise until the notch in the pulley’s
inboard rim aligns with the pointer protruding
from the oil pump housing. On 14 NV models,
where two notches (indicating 10°and 5°
BTDC respectively) are found, rotate the
crankshaft until the second notch (in thedirection of rotation -i.e. 5°BTDC) aligns. Use
white paint or similar to emphasise the pointer
and notch, to make them easier to see.
4Connect a timing light to No 1 cylinder
(nearest the timing belt end of the engine) HT
lead, also a tachometer; follow the equipment
manufacturer’s instructions for connection.
5Start the engine and allow it to idle -the
speed should be between 700 and 1000 rpm.
6On 14 NV models, aim the timing light at the
pointer and check that it is aligned with the
crankshaft pulley notch.
7On early 16 SV models, disconnect the
ignition timing basic adjustment coding plug.
This can be identified by a length of Black
wire joining Brown/Red and Brown/Yellow
wires in a connector plug clipped to the wiring
or heater/cooling system hoses beneath the
battery/ignition coil (see illustration, 16.1). This
causes the MSTS-i module to adopt its basic
adjustment mode, sending a constant firing
signal corresponding to 10°BTDC and
eliminating any advance below 2000 rpm. Aim
the timing light at the pointer and check that it
is aligned with the crankshaft pulley notch.
8On later 16 SV, C 16 NZ and C 16 NZ2
models, the coding plugs are no longer fitted.
For accurate checking, special Vauxhall test
equipment must be used which causes the
MSTS module to adopt its basic adjustment
mode.
9Without access to such equipment, it is
possible to check and adjust the ignition
timing, accurate results cannot be
guaranteed. Owners are therefore advised to
have this work carried out by a suitably
equipped Vauxhall dealer; at the very least,
make the initial setting yourself and then have
it checked as soon as possible.
10If you do attempt to check the ignition
timing yourself, note that the fixed reference
mark is now an extended line embossed on
the timing belt lower outer cover.
Adjustment
11If the notch and pointer are not aligned,
loosen the distributor clamp nut and turn the
distributor body slightly in the required
direction to align.
12Tighten the distributor clamp nut, and
check that the notch and pointer are still
aligned. 13Stop the engine, and disconnect the
timing light and tachometer.
14On 16 SV models, reconnect the basic
adjustment coding plug. On 14 NV models,
reconnect the vacuum pipe to the distributor
vacuum diaphragm unit.
Other models
15No adjustment of the ignition timing is
possible on 1.8 and 2.0 litre models, as the
adjustment is carried out automatically by the
electronic control module.
16The ignition timing can be checked by a
Vauxhall dealer using specialist dedicated test
equipment, if a fault is suspected.
22Ignition timing -adjustment
for use with unleaded petrol
3
14 NV models
1All models with the 14 NV engine have the
ignition timing adjusted for use with 95 RON
unleaded petrol before they leave the factory,
and no further adjustment is required.
2Leaded petrol (98 RON) can be used if
desired, with no adverse effects.
1.6, 1.8 and 2.0 SOHC models
Note: Models equipped with a catalytic
converter must be operated on 95 R0N
unleaded petrol at all times, and although an
octane coding plug may be fitted, it should
not be tampered with
3Models, other than 14 NV, are equipped
with an octane coding plug, which is located
Engine electrical systems 5•13
20.16B . . .and withdraw the sensor plate -
1.6 litre (Bosch distributor)
20.16C Sensor plate screw (arrowed) -
1.6 litre (Lucas distributor)
20.16A Remove the securing screws . . .20.15B . . .and disconnecting the small
wiring plug - 1.6 litre (Lucas distributor)
5

2Exhaust gas recirculation
(EGR) system - general
The system reintroduces small amounts of
exhaust gas into the combustion cycle to
reduce the generation of oxides of nitrogen
(NOx).
On C16 NZ, C16 NZ2 and C18 NZ engines,
the volume of exhaust gas reintroduced is
governed by manifold vacuum, through the
EGR valve mounted on the inlet manifold.
When the valve is opened small amounts of
exhaust gas are allowed to enter the inlet
tract, passing through ports in the cylinder
head.
On X16 SZ engines the EGR valve is
operated by an EGR module, mounted on the
left-hand side of the engine compartment
behind the battery. This module amplifies
signals received from the fuel system ECU
and operates the EGR valve electronically
providing precise control of exhaust gas
recirculation under all engine conditions.
3EGR valve (Multec system
models) - testing, removal and
refitting
2
Testing
1On C16 NZ, C16 NZ2 and C18 NZ engines,
it is recommended that the system is checked
annually, by checking the movement of the
valve’s diaphragm carrier plate as follows.
Note that the carrier plate is visible only
through the apertures in the underside of the
valve, so a battery-operated torch and small
mirror may be useful. On X16 SZ engines,
Vauxhall test equipment is necessary to check
the EGR system.
2With the engine fully warmed up to normal
operating temperature and idling, briefly open
and close the throttle. The carrier plate should
move upwards as the manifold vacuum
changes. When the engine is idling smoothly
again, press the carrier plate upwards (do this
very carefully, so that the plate is not distorted or
the diaphragm damaged). The idle speed should
drop significantly (approximately 100 rpm).
3If the valve does not respond as described,
it must be cleaned.
Removal
4Pull off the hose from the valve, then unbolt
the valve and remove it (see illustrations).
Clean away all carbon using a wire brush and
a pointed tool, but take care not to damage
the valve seat. Renew the valve gasket to
prevent induction leaks.
Refitting
5Refit the valve and reconnect the hose,
then recheck the system’s performance; if
there is no improvement, the valve must be
renewed.
4EGR valve (Simtec system) -
testing, removal and refitting
3
Note: A new gasket will be required when
refitting the valve.
Removal
1Disconnect the battery negative lead.
2Remove wiring harness and vacuum hose.
3Mark position of the valve, to ensure
correct relocation.
4Undo the 3 bolts, and remove the valve
from the dual spark ignition coil’s coolant
flange.
Refitting
5Clean the sealing surfaces of the valve and
flange.
6Refit the valve with a new gasket and line
up the marks made before removal (see
illustration).
5EGR module (X16 SZ
models) - removal and
refitting
2
Removal
1Disconnect the knock module from its
bracket (refer to Chapter 4B, if necessary),
and place to one side.
2Remove wiring plug from module. Remove
module from bracket.
Refitting
3Refitting is a reversal of removal.
6AIR pump assembly (Simtec
system) - removal and refitting
3
Removal
1Chock the rear wheels, jack up the front of
the vehicle and support it on axle stands
placed under the body side members (see
“Jacking and Vehicle Support”)
2Remove the left hand front wheel and inner
wheel arch lining.
3Loosen the hose clamp and remove the air
duct hose from the pump.
4Disconnect the battery negative lead.
5Undo the securing nuts and remove the
pump assembly from its location. Disconnect
the wiring plug.
6Remove the wiring plug from the pump’s
bracket.
7Mark the position of the pump on it’s
bracket before separating.
8Remove the fixing bolts and disconnect the
pump from it’s insulator.
9The insulator can also be checked by
removing the 3 nuts, securing the protective
shield. Before removing, mark the shield and
insulator. Replace if necessary.
10Check the pump’s air cleaner for damage.
Refitting
11Refitting is a reversal of removal. Ensure
correct alignment of the components.
7AIR cut-off valve - removal,
testing and refitting
3
Removal
1Before removal, mark on the cut-off valve,
the direction of flow towards the non-return
valve (see illustration).
2Disconnect and remove the air duct and
vacuum hoses.
3Undo the switchover valve’s bolts and
move to one side.
4C•2Fuel and exhaust systems - exhaust and emissions
3.4 Disconnecting the vacuum hose from
the exhaust gas recirculation valve
4.6 EGR valve
1 Valve 2 Gasket
3.4B Withdrawing the exhaust gas
recirculation valve

4The cut-off valve can now be removed from
the bracket.
Testing
5To test the cut-off valve a vacuum hand
pump with gauge will be required. If available,
connect to the cut-off valve and ensure that
air through-flow aperture is fully open.
Refitting
6Refitting is a reversal of removal. Ensure
valve is fitted in the correct direction.
8AIR switchover valve -
removal and refitting
3
Removal
1Disconnect the battery negative lead.
2Disconnect wiring plug from the valve.
3Mark the location of the vacuum hoses
before removing them from the valve.
4After disconnecting the hoses undo the two
bolts, and remove them from its bracket.
Refitting
5Refitting is a reversal of removal. Ensure
hoses are fitted correctly (see illustration).
9AIR pipe and non-return
valve - removal and refitting
3
Note:New air pipe washers will be required
when refitting.
Removal
1Remove the non-return valve air duct hose.
2Undo the bolts engine lifting eye bracket,
and turn the bracket on to its left hand side.
3Remove the pipe support bracket by
releasing its three bolts.
4Remove the heat shield that is secured by
two bolts.
5The air pipe can now be removed by
releasing the two securing bolts.
6If necessary the non-return valve can now
be disconnected.
7Carefully clamp the pipe using a vice with
protective jaws. Unbolt the valve from the
pipe, clean and inspect for damage.
Refitting
8Before refitting, coat the threads of the non-
return valve with sealing compound (i.e.
Vauxhall part no. 90094714).
9Use new washers when refitting the pipe,
(take care as the washers have sharp edges).
Coat the pipe mounting bolts with assembly
paste (i.e. Vauxhall part no. 90513210), before
refitting.
10Refitting is a reversal of removal.
Retighten to correct torque as shown in Spec-
ifications.
10Catalytic converter -
description, general and
precautions
Note: The catalytic converter is not a filter. It
creates a chemical reaction, but it is not
affected by that reaction.
Description
1Certain models are available with a catalytic
converter, to reduce exhaust emissions.
These models can be identified by a ‘C’ or ‘X’,
prefixing the engine code.
2The purpose of the catalytic converter is to
change potentially harmful hydrocarbon andcarbon monoxide exhaust gases into harmless
gases and water vapour. The converter
consists of a stainless steel canister containing
a catalyst-coated honeycomb ceramic. The
catalyst is a mixture of three precious metals,
platinum, palladium and rhodium.
3The exhaust gases pass freely through the
honeycomb, where the catalyst speeds up the
chemical change of the exhaust gases,
without being permanently altered itself.
4To avoid damage to the catalyst, the engine
must be kept properly tuned, and unleaded
petrol must always be used. Normal leaded
petrol will “poison” the catalyst, and must not
be used.
5To enable the Motronic engine management
system to achieve complete combustion of the
fuel mixture, and thus to minimise exhaust
emissions, an oxygen sensor is fitted in the
exhaust gas stream. The sensor monitors the
oxygen level in the exhaust gas, and sends a
signal to the Motronic module. The module
constantly alters the fuel/air mixture within a
narrow band to reduce emissions, and to allow
the catalytic converter to operate at maximum
efficiency. No adjustment of idle mixture is
therefore possible on models fitted with a
catalytic converter.
General
6Ninety-nine per cent of exhaust gases, from
a petrol engine (however efficient or well
tuned), consists of nitrogen (N
2), carbon
dioxide (CO
2), oxygen (O2), other inert gases
and water vapour (H
2O). The remaining 1% is
made up of the noxious materials that are
currently seen (except CO
2), as the major
polluters of the environment. Carbon
monoxide (CO), unburned hydrocarbons (HC),
oxides of nitrogen (NOx) and some solid
matter, including a small lead content.
7The device most commonly used to clean
up vehicle exhausts is the catalytic converter.
It is fitted into the vehicle’s exhaust system
and uses precious metals (platinum and
palladium or rhodium) as catalysts to speed
up the reaction between the pollutants and
the oxygen in the exhaust gases. CO and HC
being oxidised to form H
2O and CO2and (in
the three-way type of catalytic converter) NOx
being reduced to N
2.
8The converter consists of an element of
ceramic honeycomb, coated with a
combination of precious metals in such a way
as to produce a vast surface area over which
the exhaust gases must flow. The three-way
closed-loop type converter fitted to these
models can remove over 90% of pollutants.
9The catalytic converter is a reliable and
simple device that needs no maintenance.
However there are some facts that an owner
should be aware if the converter is to function
properly for its full service life (see
illustration).
a)DO NOT use leaded petrol in a vehicle
equipped with a catalytic converter. The
lead will coat the precious metals,
reducing their converting efficiency and
will eventually destroy the converter.
Fuel and exhaust systems - exhaust and emissions 4C•3
10.9 The catalytic converter is protected
by heat shields
8.5 AIR switchover valve
1 Connection to brake servo vacuum hose
2 Connection to cut-off valve
7.1 AIR cut-off valve
1 Connection to AIR pump
2 Connection to AIR switchover valve
3 Connection to AIR non-return valve
4C

Idle settings (continued)
Idle mixture (CO content):
20 NE and 20 SEH . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.0 max.
20 XEJ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.7 to 1.2%
All other models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.3 % (at 2800 to 3200 rpm)
Fuel Pressure (regulator vacuum hose connected)
Multec . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.76 bar
Motronic 4.1:
Feed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.3 to 2.7 bar
Return . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.3 to 1.5 bar
Motronic 1.5:
Feed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1.8 to 2.2 bar
Return . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.3 to 1.5 bar
Motronic 2.5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.0 to 2.2 bar
Motronic 2.8 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.2 to 2.7 bar
Simtec 56.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .not available
Torque wrench settingsNmlbf ft
All specifications as for carburettor models except for the following:
Bracket, tank vent valve to coolant flange . . . . . . . . . . . . . . . . . . . . . . .86
Fuel distributor pipe to inlet manifold . . . . . . . . . . . . . . . . . . . . . . . . . . .86
Fuel flow damper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2015
Fuel injector retainer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .32
Fuel pressure regulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.52
Fuel pump clamp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .43
Idle air control stepper motor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2.52
Knock sensor (X16 SZ) to block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1310
Oxygen sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3022
Throttle body mounting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2015
Throttle body upper-to-lower section . . . . . . . . . . . . . . . . . . . . . . . . . . .64.5
Throttle potentiometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21.5
Throttle valve housing to inlet manifold . . . . . . . . . . . . . . . . . . . . . . . . .97
1General description
General
1All engines available within the Cavalier
range can be operated on unleaded petrol.
Refer to Chapter 5 for further details. Note
that models fitted with a catalytic converter
must only be operated on unleaded petrol,
and leaded petrol must not be used. Models
with catalytic converter can be identified by
the engine code, which is prefixed by the
letter ‘C’ or ‘X’.
Multec system
Note: There is no provision for the adjustment
or alteration of the idle speed; if checking the
idle speed, remember that it may vary
constantly under ECU control.
2The Multec system is essentially a simple
method of air/fuel metering, replacing the
carburettor with a single injector mounted in a
throttle body. This type of system is therefore
also known as Throttle Body Injection (TBi),
Central Fuel Injection (CFi) or single-(or
mono-) point injection. The whole system is
best explained if considered as three
sub-systems, these being fuel delivery, air
metering and electrical control.
3The fuel delivery system incorporates the
fuel tank (with the electric fuel pumpimmersed inside it), the fuel filter, the fuel
injector and pressure regulator (mounted in
the throttle body), and the hoses and pipes
connecting them. When the ignition is
switched on (or when the engine is cranking,
on X16 SZ engines) the pump is supplied with
voltage, by way of the pump relay and fuse
11, under the control of the Electronic Control
Unit (ECU). The pump feeds through the fuel
filter to the injector. Fuel pressure is controlled
by the pressure regulator, which lifts to allow
excess fuel to return to the tank.
4The air metering system includes the inlet air
temperature control system and the air
cleaner, but its main components are in the
throttle body assembly. This incorporates the
injector, which sprays fuel onto the back of the
throttle valve, the throttle potentiometer. This
is linked to the throttle valve spindle and sends
the ECU information on the rate of throttle
opening by transmitting a varying voltage. The
idle air control stepper motor is controlled by
the ECU to maintain the idle speed.
5The electrical side of the fuel injection
system consists of the ECU and all the
sensors that provide it with information, plus
the actuators by which it controls the whole
system’s operation. The basic method of
operation is as follows; note that the ignition
system is controlled by the same ECU.
6The manifold absolute pressure sensor is
connected by a hose to the inlet manifold.
Variations in manifold pressure are converted
into graduated electrical signals that are usedby the ECU to determine the load on the
engine. The throttle valve potentiometer is
explained above.
7Information on engine speed and
crankshaft position comes from the distributor
on C16 NZ engines and from the crankshaft
speed/position sensor on C16 NZ2, X16 SZ
and C18 NZ engines.
8An odometer frequency sensor provides the
ECU with information on the vehicle’s road
speed, and the coolant temperature sensor
provides it with the engine temperature. A
knock sensor located in the cylinder block
between cylinders 2 and 3 on the X16 SZ
engine provides additional information to the
ECU by detecting pre-ignition (detonation)
during the combustion process.
9All these signals are compared by the ECU
with set values pre-programmed (mapped)
into its memory. Considering this information,
the ECU selects the response appropriate to
those values. It controls the ignition amplifier
module by varying the ignition timing as
required. The fuel injector is controlled by
varying its pulse width the time the injector is
held open, to provide a richer or weaker
mixture, as appropriate. The idle air control
stepper motor controls the idle speed. The
fuel pump relay controls the fuel delivery and
the oxygen sensor, accordingly. The mixture,
idle speed and ignition timing are constantly
varied by the ECU to provide the best settings
for cranking, starting and engine warm-up
(with either a hot or cold engine), idling,
4B•2Fuel and exhaust systems - fuel injection models