Dacia Solenza (engine E7J). Manual - part 28

IGNITION AND  INJECTION

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At vehicles equipped with diagnostic system OBD (On Board Diagnostic), when detecting a

cause 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 OBD system is taking into consideration during its operation of the performing the follow-

ing diagnostics:

- electric diagnostics;
- combustion misfires diagnostics
- functional diagnostic of the upstream oxygen sensor;
- catalyst diagnostic.

Electric 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
order to a.m. diagnostics commencement:

- water/air temperature conditions;
- vehicle speed condition (evaluation field);
- engine parameters conditions (inlet manifold pressure, values fields and stability);
- starting timer.

OBD information management is completing classical electric failures management.

In order to meet this requirement, it is obligatory the OBD operation as per following way:

- lighting (or blinking for some failures) of the OBD indicator;
- memorizing of the OBD failures by UCE injection.

                  EFFECTS ON DIAGNOSTIC AND REPARATIONS

 During reparation of vehicles equipped with OBD system, a special attention will be given to

avoid the OBD 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 are ”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 results by means of the CLIP tester. Any  contact setting off
before reading the test results, will lead to their wrong interpretation.

“On Board Diagnostic” system characteristics

IGNITION AND  INJECTION

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CONDITIONS OF OBD  INDICATOR LIGHTING

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

further 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

failure in cause will remain memorized by the UCE injection.
In order to cancel the failures memorized by the UCE  injection, failures must not be detected
during 40 consecutive tests (or to perform the erasing of the memorized failures, by means of the
CLIP tester).

OBSERVATION: 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

failure detection;

- random character (non-permanent) of the respective failure.

“On Board Diagnostic” lighting conditions

IGNITION AND  INJECTION

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DIAGNOSTIC CONDITIONS

If when 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.
- water temperature, red by the water temperature sensor, is not situated between –6° and

119°C.

- atmospheric 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  failures of electric nature.
- Erase  all failures by means of the CLIP tester
- Perform the “teaching” stage of all adaptive values by the injection system (if necessary).

OBD  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 UCE

INJECTION FOR OBD DIAGNOSTIC

〈 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 ENRICHING ADAPTIVE LEARNING

In order to do that, it is necessary that vehicle is running observing in the same time the pressure
ranges mentioned in the chapter “ Enriching adaptive correction”.

〈 State “ET202 = OBD diagnostic of combustion misfires taken into consideration” must be

ACTIVE.

“On Board Diagnostic” diagnostic conditions

IGNITION AND  INJECTION

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This diagnostic may detect:

- spark plug fouling or smoking,
- fouling or modification from the normal value of the injectors flow,
- fuel supply system abnormalities (pressure controller, fuel pump,..)
- problems with the electric connections for controlling fuel supply circuits and the injection.

The diagnostic 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.
This 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:

- destructive combustion misfires, which are causing the catalyst damage. These are gener-

ating the immediate blinking of the OBD indicator.

- Polluting combustion misfires, leading to exceeding a pre-established OBD pollution limit.

These are generating the  permanent lighting of the OBD  indicator, if  the  cause detection is

taken place during three consecutive running.

DETECTION 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
contact 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:

ET014 Cylinder 1 recognition----------------------------------------------------------------- DONE
ET202 OBD diagnostic of combustion misfires taken into consideration--------------ACTIVE
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 setting on is imposed (key in M

position) before reading the results by means of the CLIP tester. Any contact setting off
before 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-

fires, refer to the diagnostic method related to this symptom.

CONFIRMATION OF THE REPARATION PERFORMING

- Check  by  means of the CLIP tester, the bellow states, which must have the following

configuration:
ET014 Cylinder 1 recognition -------------------------------------------------------------------- DONE
ET202 OBD diagnostic of combustion misfires taken into consideration ----------------- ACTIVE

- No failures is detected by the CLIP tester, and the OBD indicator must be off.

Diagnostic of combustion misfires detection