2004 DACIA SOLENZA Repair Manual

IGNITION AND INJECTION
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AIR CONDITIONING UNIT IS USING A COMPRESSOR
WITH VARIAB LE DI SPLACE M ENT
Th e connections injection/air conditioning, are the followings:
- pin 46 of the injection computer is receiving the information “ air conditioning
re que st” further to the air conditioning switch acting;
- pin 10 of the injection computer will transmit the coupling control of the air
co nditioning compressor by means of the “A” relay, if the coupling authorization conditions are
accomplished.
The information “power absorbed by compressor” displayed when performing diagnostic by
means of the CLIP tester, is related to the couple value taken by the compressor. This is of 300-
5000W, the minimal displayed value being of 300 W, regardless the compressor coupled / unc oupled
c ondition.
Th e injection computer is forbidding the compressor coupling in the following situations:
-at less than 16 seconds from engine starting;
-subject to the power requested to the engine by the vehicle driver.
-when th e acceleration pedal is fully pressed;
-i f the engine RPM is lowering till 550 rot/min (compressor is again coupling if the RPM is
r eachi ng to 1800 rot/min);
-if the wa ter temperature has increased to over 110° C;
-if the engi ne RPM is exceeding 6000 rot/min.
Injection / air conditioning strategy
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IGNITION AND INJECTION
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IDLING REGIME CORRECT ION SUB JECT TO B ATTERY VOLTAGE AND TO
ELECTRI C BA LANCE ON VEHICL E.
Th is correction is dedicated to the compensation of the voltage drop due to the electric consumers
starting, when the battery is weaker charged. In this purpose, engine RPM is increased, allowing in
this way the alternator rotation increase and consequently of the battery voltage.
More the lower is the voltage, more important the applied correction is. So, a variable correction
is applied, starting when voltage is reaching 12,8 V. The correction is starting from the nominal
idling RPM and may increase with maximum 150 rot/min additional.
Idling regime correction
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IGNITION AND INJECTION
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PRINCIPLE
In engine normal operation conditions at warm, the RC O value is varying between a high and
a low limit, in order to obtain the nominal idling regime. Further to an operation dispersion
(ru nning in, engine clogging, etc), it may be possible that RCO idling value to be situated next to
the lower and higher values. The ad aptive correction of the “RCO idling ” parameter is allowing obtaining of slow variations
of the engine air requirement, so that RCO value centering on an average nominal vale is obtained.
Th is correction is becoming effective unless the water temperature is over 80°C, at 20 seconds
after engine starting and if it is in the nominal idling adjustment phase.
“R CO IDLING” AND “ IDLING EN RICHING ADAPTATION” VALUES
PARA M E T ER RE COM MENDE D VAL UE
PR006: Engine regime 750 rot/min
PR022: RCO idling 5%< X < 12%
PR031: Idling enriching adaptation 80 < X < 176
At each engine stopping, the injection computer is controlling the performing of a new position-
ing of the step-by-step engine, bringing it to the bottom limit. This function so called “re-setting”, is
main tained for 8 seconds.
INTERPRETATION OF T HE PREV IOUSLY M ENT IONED PARAM ETERS
In the situation of an air excess (infiltration air, valve body inadequate attachment, etc), the idling
re gi me will increase and the “RCO idling” va lue will decrease in order to return to the nominal
idling regime. The value of the RC O idling adaptive correction will decrease in order to centering
again the id ling adjustment operation.
In case of an air lack (clogging, etc) the reasoning is opposite: “ RCO idling” is increasing, and
the value of the “ RCO idling” adaptive correction will increase in order to center again the idling
opera tion on an average nominal value.
IMPORTANT: After erasing the failures memorized by the injection computer, it is necessary
to start the engine then stop it, in order to achieve in this way the re-setting of the step-by-step
en gine. Start then again the engine and let it idle run until reaching the nominal idling regime, in
or der to achieve a correct re-setting of the adaptive correction.
Idling regime adaptive correction
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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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IGNITION AND INJECTION
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PRINCI PLE
When the engine is in “closed loop” phase, the enriching adjustment is correcting the injection
time in order to be able to obtain a fuel mixture with the enriching as close as possible to 1. The
co rrec tion value is fluctuating around the value 128, within the limits 0 and 255.
Although, variations in time of the components elements parameter of the injection system may
occur, this leading to the enriching correction displacement towards 0 or 255, in order to maintain
the enrichment at the value 1. The adaptive correction is allowing the “resetting” of the injection chart in order to bring the
enrichment adju stment to the average value 128 and the achievement of an effective constant
correc tion for the enrichment or impoverishment of the fuel mixture.
The adap tive correction of the enrichment adjustment is divided into two components:
-p reponderant adaptive correction at engine medium or high charges (adaptive enriching
during running); -prepo nderant adaptive correction at engine idling or small charges (adaptive enriching
during idling).
The adap tive corrections are considering the value 128 as an average value after performing
the activation (after erasing the memorized failures) and they have for the next parameters, the
following limit va lues:
PR030 = Adaptive enriching during running 80< X < 176
PR031 = Adaptive correction during idling 80 < X < 176.
The ad apti ve corrections are not applied unless the engine is warm (water temperature > 80°C),
and it is in the “closed loop” phase and the pressure from the inlet manifold is in a certain interval.
It is necessary that engine has been run in “closed loop” phase in many of the inlet manifold
pre ssure areas, for which the adaptive correction evolution is starting the compensation of the
engine running enriching dispersions.
Therefor e, further to UCE injection re-activation, after erasing the memorized failures, when
the values PR030 and PR031 are 128, it will be necessary that a specific road test is to be per-
formed.
Enriching adaptive correction
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IGNITION AND INJECTION
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ROAD TEST
Test performing conditions: -warm engine ( water temperature > 80°C);
-engine RPM not exceeding 4000 rot/min.
For this test, it is recommended starting from a sufficient low engine RPM, in gearbox third or
fourth gear, accelerating then progressively in order to obtain a pressure stability in th e inlet (PR001
= inlet manifold pressure) for 10 seconds in each area, as per next table:
Enriching adaptive correction
Area 1 Area 2Area 3Ar ea 4Area 5
(mbar) (mbar) (mbar) (mbar) (mbar)
250-------------- 399 ---------------- 517 ----------------- 635 ----------------- 735 -------------- 873
Average 325 Average 458 Average 576 Average 694 Average 813
After performing this test, the corrections will become effective.
PR031 parameter (adaptive enriching at idling) is more fluctuating in the idling and small charges
phases, and PR030 parameter (adaptive enriching during running) is more fluctuating in the mo-
ment of medium and full charges, but both parameters are active in all areas of inlet manifold
pressure evolution.
It is necessary that road test to be followed by a normal driving running, constant and fluctuate,
on a 5-10 Km.
After test performing, connect the CLIP tester and refer to the values of PR030 and PR031
pa rame ters. If their values are initially at 128, after correct performing the road test, they must
chan ge. Contrary, perform again the road test, strictly observing the imposed conditions.
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IGNITION AND INJECTION
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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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