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Injection system
WATER TEMPERATURE SENSOR
The water temperature sensor ( 1) is sending to UCE injection the information regarding water tempera-
tu re, and another information is sent to the indicator from the instrument panel, which will show the water
tem perature.
In case of an alert regarding the water temperature, UCE injection will control the lightening of
the water temperature indicator from the instrument panel.
Subject to water temperature, UCE injection will control:
- injection system;
- relays for controlling the engine cooling fan.
When setting the contact on, the water temperature indicator located on the instrument panel,
will be lighted for 3 seconds, then it will turn off.
1
1
If after the contact is set off, in the next 2 minutes from engine stopping, the water temperature
is reaching 102 °C, and t hen the injection computer i s control ling t he starting of the e ngine
cooling fan at low speed. When the temperature is lowering at 95°C, the engine cooling fan stopping will be controlled;
its operation must not exceed 10 minutes after engine stopping.
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MU LTI-POINT INJE CT ION CHARACT E RISTICS
〈 SIRIUS 32 with 90 pins computer is managing the ignition and the injection.
〈 For diagnostic, CLIP Sagem tester is to be used.
〈 The injection system in use is a sequential multi-point type, injection and ignition phases
controlling being based on the SIRIUS 32 computer program logic, starting from the signal received
from the RPM sensor.
〈The pr esence of the anti-pollution indicator OBD on the instrument panel, that is lighted for
3 seconds when setting the contact on, is specific to the vehicles observing pollution norms EURO
2000. The injection computer of these vehicles is provided with diagnostic system type OBD (“ On
Board Diagnostic).
〈 Idling regime correction is subject to:
-c limate maintenance on/off control (air conditioning)
-e lectrical balance on vehicle, as a result of connecting different electric consumers.
〈 EURO 2000 specific vehicles are provided with two oxygen sensors located in front of the
cata lyst (upstream oxygen sensor) and after catalyst (downstream oxygen sensor).
〈 At EURO 2000 specific vehicles, the fuel supply is performed at constant pressure (3.5 ±
0.2 bar), the pressure controller placed in the fuel tank being provided for this purpose.
Chara cteristics
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IGNITION AND INJECTION
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The e ngines equipped with UCE injection type SIRIUS 32 are provided with oxygen sensors, as
follows:
-one up stream oxygen sensor – for engines corresponding to EURO 96 de-pollution norms.
- one upstream oxygen sensor and one downstream oxygen sensor – for engine s corresponding
to EURO 2000 de-pollution norms.
OXYGEN SENSORS HEATING
Oxygen sensors heating control is given by UCE injection as follows: -for up stream oxygen sensor – starting with engine starting.
-f or downstream oxygen sensor – after a certain time from engine starting, imposed by the
UCE injection charts, being subject to engine RPM and water temperature, red only when the
accelera tion pedal is not released.
UPSTREAM OXYGEN SENSOR VOLTAGE
After connecting the CLIP tester select “ Injection Diagnostic” and refer to “PR009 parameter:
Upstream oxygen sensor voltage”. The displayed value, expressed in mV, is representing the voltage
supplied towards UCE injection by the oxygen sensor placed upstream as the catalyst. When the
engine is running in the “closed loop” phase, voltage must fluctuate quickly between the following
lim i ts :
-20 mV ± 50 for poor fuel mixture;
-840 mV ± 70 for rich fuel mixture.
Smaller is the difference between these two limits, less good the sensor information is
(g en erally this difference is of 500 mV).
DOWNSTREAM OXYGEN SENSOR VOLTAGE
After connecting the CLIP tester select “ Injection Diagnostic” and refer to “PR010 param-
eter: Downstream oxygen sensor voltage”. The displayed value, expressed in mV, is representing
the voltage supplied towards UCE injection by the oxygen sensor placed after the catalyst. This
sensor has the purpose to catalyst diagnostic and to perform a second checking, more exactly, of
the fuel mixture enriching. This function is becoming active only after a certain time of engine
running at warm and it is not active in the engine idling phase.
When the engine is running in “closed loop” phase and at stabilized speed, voltage must fluctuate
ha ving between the maximal and minimal limits a difference of 600-mV ± 100. At deceleration,
voltage mu st be under 200 mV.
Enriching adjustment
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IGNITION AND INJECTION
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ENRICHING CORRECTION
After connecting the CLIP tester, select “Injection diagnostic” and refer to “PR035 parameter:
En riching correction value”. The value displayed is representing the corrections average imposed
by the UCE injection, subject to the fuel mixture enriching, red by the upstream oxygen sensor (the
sensor is analyzing the oxygen concentration from the exhaust gases). The co rrection value has an average value of 128 and the limits are 0 and 255:
-a value lower than 128 has as result, the request for fuel mixture impoverishment
-a value greater than 128 have as results the request for fuel mixture enriching.
ENRI CHING ADJUSTMEN T PHASE
Admission in the enriching adjustment phase is becoming effective after a certain time from
en gine starting, with the condition that water temperature is reaching to over 22°C and 28 seconds
from engine star ting have passed.
If ad m ission in the enriching adjustment phase is not effective, the value of PR035 parameter is
128.
Even when conditions for enriching adjustment phase beginning are accomplished, UCE injec-
tion however, will not take into account the voltage supplied by the downstream oxygen sensor, in
the following situations: -acceleration pedal fully pressed: PR035 is variable and higher than 128;
-sudden ac celeration: PR035 is variable and higher than 128;
-d ecelera tion (engine braking) followed by UCE injection detection of the position ”free” of
the acceleration pedal: PR035 = 128; -down stream oxygen sensor failure: PR035 = 128.
WORKING PROCEDURE “DAMAGED” IN CASE OF DOWNSTREAM OXYGEN SENSOR FAILURE
When the voltage supplied towards UCE injection by the downstream oxygen sensor is not
correct (showing small or not at all variations) in the enriching adjustment phase, then UCE injec-
tion will not pass to the working procedure “damaged” (PR035 = 128) unless the failure has been
rec ognized as being present for 10 seconds. Only in these conditions, the failure will be memorized
by the UCE injection.
If UC E injection is detecting a present failure of the oxygen sensor and if this failure has been
al rea dy memorized, then UCE injection will come out from the enriching adjustment phase, passing
to phase “open loop”. In this situation PR035 parameter will not show variations and will have the
value 128.
Enriching adjustment
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At vehicles equipped with diagnostic system OBD (On Board Diagnostic), when detecting a
caus e leading to an excessive pollution, on the instrument panel the OBD indicator will be on,
indicating to the driver that vehicle must be repaired to eliminate the pollution cause.
The OB D system is taking into consideration during its operation of the performing the follow-
ing diagnostics: -electric diagnostics;
-c ombustion misfires diagnostics
-f unc tional diagnostic of the upstream oxygen sensor;
-c atalyst diagnostic.
El ectric and combustion misfires diagnostics are permanently performed.
Functional diagnostic of the upstream oxygen sensor and catalyst diagnostic are performed one
time only during one driving, subject to reaching the imposed values of the following parameters, in
or der to a.m. diagnostics commencement:
-water /air temperature conditions;
-v ehicle speed condition (evaluation field);
-e ngine parameters conditions (inlet manifold pressure, values fields and stability);
- starting timer.
OBD information management is completing classical electric failures management.
In orde r to meet this requirement, it is obligatory the OBD operation as per following way:
- lighting (or blinking for some failures) of the OBD indicator;
-memoriz ing of the OBD failures by UCE injection.
EFFEC TS ON DIAGNOSTIC AND REPARATIONS
During reparation of vehicles equipped with OBD system, a special attention will be given to
a void the OB D indicator lighting after reparations performing and returning the vehicle to the end-
user.
Certain failures can be noticed only during driving, this being the moment when the adaptive
values ar e ”learned ”, so: The reparation validation is obligatory imposed .
REMARK: all electric failures leading to pollution limit exceeding, will produce the OBD
indicator lighting.
ATTENTION: after each test performing, the contact setting on is imposed (key in M
position) before reading the res ults by means of the C LIP tester. Any contact sett ing off
be fore reading the test results, will lead to their wrong interpretation.
“On Board D iagnostic” system c haracteristics
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DIAGNOSTIC CONDI T IONS
If wh en setting on the contact, with stopped engine, one of the following conditions is accom-
plished: -air temperature, red by the air temperature sensor, is not situated between –6° and 119°C.
-w ater temperature, red by the water temperature sensor, is not situated between –6° and
119°C.
-atmosphe ric pressure is under 775mbar,
then the OBD diagnostics are not authorized until the next contact setting on. In order to have a correct operation of the OBD diagnostic system, no electric failure of the
injection system must exist, even if the lighting of the OBD indicator is not established. The catalyst and oxygen sensor diagnostics can not be performed in the same time, but one
after other.
When the catalyst or oxygen sensor diagnostics are under operation, the canister purging valve
is closed, and the adaptive values are “blocked” at the last existent value prior to a.m. diagnostics
starting. TESTS PERFORMING LOGIC
-Solve fa ilures of electric nature.
-Erase a ll failures by means of the CLIP tester
-Perform the “teaching” stage of all adaptive values by the injection system (if necessary).
OB D COMPLETE ACTIVATION BY MEANS OF CLIP TESTER
-Erase all memorized failures.
-Erase the “learned” values from UCE injection if further to an intervention on an injection
system component, a disturbance of the “learned” values took place (step-by-step engine, flywheel
or RPM sensor, etc).
RETENTIONS (“LEARNINGS”) NECESSARY FOR UCEINJECT ION FOR OBD DI AGNOSTIC
〈 COUPLING/SUPPLY RATE LEARNING (state “ET014 = cylinder recognition 1” is PER-
FORMED with running engine). This is to be performed as following:
-a deceleration with “cutting” of the petrol injection in the third gear of the gearbox, be-
tween 3000-3500 rot/min for at least 2 seconds,
-a second deceleration with ”cutting” of the petrol injection in the third gear of the gearbox,
between 2400-2000 rot/min, for at least 2 seconds.
〈 MIXTURE ENRI CHING ADAPTIVE LEARNING
In order to do that, it is necessary that vehicle is running observing in the same time the pressure
ranges men tioned in the chapter “ Enriching adaptive correction”.
〈 State “ET202 = OBD diagnostic of combustion misfires taken into consideration” must be
AC TIVE.
“On Board Diagnostic” diagnostic conditions
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The purpose of the catalyst diagnostic is the detection of the disturbances leading to exceeding
an OBD step due to HC pollution emissions.
Th e ca talyst storage capacity of the oxygen is the indicator of its condition. When the catalyst is
beginnin g to ”age”, the storage capacity of the oxygen is diminishing, in the same time with the
dimin ishing of the treatment capacity of the pollution gases.
IMPOSED CONDITIONS FOR DIAGNOSTIC STARTING
Th e ca talyst diagnostic can be not performed but after a certain time of engine operation and
on ly if the preliminary conditions, when setting the contact on, are accomplished and preserved:
-no electr ic failure
-c ylinder’s recognition performed
-n o detected combustion misfire.
-n on-performing of the catalyst diagnostic after contact setting on.
-correct performing of the “learnings” by the UCE injection.
-water temper ature to be over 75°C
Catalyst diagnostic
Engine Speed Regime Manifold pressure Stabilization period Time before authorization
(Km/h) (rot/min) (mbar) (s ec) (min)
E7J 63-130 1792-4000 430-739 1117
FAILURES DETECT ION
Th e diagnostic is to be performed on a stabilized range in the fifth gear, at the speed of 70 Km/h.
When the diagnostic starting conditions are accomplished, excitation peaks are applied, which is
le ad ing to th e oxygen bubbles sending to the catalyst. If the catalyst is good, it w ill absorb the
ox ygen and the tension of the downstream oxygen sensor will remain at an average value. If the
catalyst is used, it will reject the oxygen and the oxygen sensor will wrongly define the phenom-
en on. The oxygen sensor tension will fluctuate. If the failures is three consecutively times con-
firmed, th e OBD indicator would be on.
Th e test duration will be not exceeding 52 seconds.
ATTENTION: after performing this tes t, the contact s etting on is imposed (key in M
position) before reading the res ults by means of the C LIP tester. Any contact sett ing off
be fore reading the test results, will lead to their wrong interpretation.
If after test performing, the CLIP tester is noticing the presence of the combustion mis-
f ires, refer to the diagnostic method related to this symptom.
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RE PARATI ON CONFI RM ATI ON
Check by means of the CLIP tester, the bellow states, which must have the following configu-
ration:
- ET 103: Catalyst diagnostic taken into consideration ------------------------------ ACTIVE
- ET1 07: Catalyst diagnostic performed ---------------------------------------------- ACTIVE
-n o functional failure of the catalyst is detected by the CLIP tester.
Th e purpose of the oxygen sensor diagnostic is to detect a disturbance leading to exceeding the
OBD step, caused by the HC polluting emissions. Diagnostic is performed by measuring and
co mparing the oscillating periods of the values red by the oxygen sensors.
Th e po ssible degradations of the oxygen sensors, are of two types:
-m echanical degradation of the electric component (case, wire broke) which is to be de-
fined as electric failure.
-c hemical degradation f the component, leading to a retardation of the sensor responding
time, consequently an increase of the minimal/maximal oscillating period. When the test conditions are accomplished, perform the average of the periods pointed out by
the sensor, retrieving the parasite effects, which are compared with an OBD step average period.
TEST PE RFORM ING CONDITIONS
Diagnostic of the oxygen sensor can be not performed but after a certain engine running time
an d in some specific established operation conditions and if the preliminary conditions, achieved
when setting the contact n, are achieved and preserved: -no electr ic failure
-c orrect performing of the “learnings” by the UCE injection and of the cylinders recognition.
-n o detected combustion misfire.
-N on-performing of the oxygen sensor diagnostic after contact setting on.
-water temper ature to be over 75°C
Engine Speed Regime Manifold pressure Stabilization period Time before authorization (Km/h) (rot/min) (mbar) (s ec)(min)
Oxygen sensor diagnostic
E7J 63-130 1792-3712 299-799 5 14
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