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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IGNITION AND INJECTION
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CONDITIONS OF OBD INDI CATOR L IGHTING
During driving it is possible that certain functions are not subject to diagnostic (for instance due
to crowded traffic driving).
Indicator lighting -it is occurring if the same OBD failure is detected during three consecutive driving or
fu rther to an electric failure.
Indicator blinking -it is occurring if combustion misfires are detected, that may cause the catalyst damage.
Indicator off
- it is occurring if the OBD failure is not happening during three consecutive driving, but the
fa ilure in cause will remain memorized by the UCE injection.
In orde r to cancel the failures memorized by the UCE injection, failures must not be detected
du ring 40 consecutive tests (or to perform the erasing of the memorized failures, by means of the
CLIP te st er).
O BSERVATION : if a previously detected failure has been not detected again, then the cause
may be: -driving type performed by the end-user, not driving exactly in the conditions imposed for
fa ilure detection;
-rando m character (non-permanent) of the respective failure.
“On Board Diagnostic” lighting conditions
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IGNITION AND INJECTION
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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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IGNITION AND INJECTION
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This diagnostic may detect:
-spark plug fouling or smoking,
-fou ling or modification from the normal value of the injectors flow,
-f uel supply system abnormalities (pressure controller, fuel pump,..)
-pr oblems with the electric connections for controlling fuel supply circuits and the injection.
Th e di ag nostic is performed by variations measurement of the engine prompt rotation speed.
Notice of a couple decrease is allowing the defective combustion recognition as failure cause.
Th is diagnostic is done almost permanently during driving. Non accomplishment of the diagnos-
tic or recognition of the existence of failure, is leading to other OBD diagnostics inhibition. This diagnostic is enabling the identification of two types of failures:
-de structive combustion misfires, which are causing the catalyst damage. These are gener-
ating the immediate blinking of the OBD indicator. -Polluting combustion misfires, leading to e xceeding a pre-established OBD pollution limit.
These ar e generating the permanent lighting of the OBD indicator, if the cause detection is
taken place during three consecutive running.
DE T ECT ION CONDITIONS
At the beginning, it must be checked if the “learning” stages of the adaptive values by the UCE
injection have been correctly performed. Also the preliminary conditions imposed when setting the
co ntact on and those from checking moment, must be accomplished.
Check by means of the CLIP tester if the bellow mentioned states are in the following configu-
ration:
ET0 14 Cylinder 1 recognition----------------------------------------------------------------- DONE
ET2 02 OBD diagnostic of combustion misfires taken into consideration--------------AC TIVE
Detection is accomplished after the water temperature is exceeding 75°C, at three rotation
steps, between idling and 4500 rot/min. It is also possible, test performing by maintaining the engine
at idling for a period of time of 11 minutes.
ATTENTION: after performing this test, the contact set ting on is imposed (key in M
position) before reading the r esults by means of the CLI P t ester. Any contact set ting 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.
CONFIRM ATION OF THE RE PARATION PE RFORM ING
-Check by m eans of the CLIP tester, the bellow states, which must have the following
c onfiguration:
ET0 14 Cylinder 1 recognition -------------------------------------------------------------------- DONE
ET2 02 OBD diagnostic of combustion misfires taken into consideration ----------------- AC TIVE
-N o failures is detected by the CLIP tester, and the OBD indicator must be off.
Diagnostic of combustion misfires detection
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IGNITION AND INJECTION
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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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