14E7J-A-2/60 ENGINE ANTI-POLLUTION
Check at idling if there is a depression, by fitting a pressure gauge (-3…+ 3 bars) at the
purging valve exit (B) t owards canister. Is there any depression?
YES - Set off the contact . Using a vacuum pump, apply a 500 mbars depression at
the (C ) connection of t he purging valve. The value of t he re ad depre ssion must not vary
more than 10 mbars within 30 seconds. If change i s more than 10 mbars, then purging
valve is damaged and must be replaced. Valve cleaning of small active carbon part icles
may be tried, by low-pressure compressed air blowing at the valve (B) connection NO - When conditions of purging valve controlling are accomplished and this one
does not open, c heck its control electric circ uit ( be tween UCE i njection pin 4 and purging
valve), from continuity or short-circuit point of view. The RCO value of the signal received by the purging valve from the computer, may be
read by means of the CLIP tester in PROL 23. The m inimal value is of 0.7% (corresponding
to the closed position of the purging valve).
P
LACING - DIS M O UNT ING
Both t he c arbon c anister and the draining va lve are mounted by means of a stand on the
lining of the right-side front wing of the car.
The channellings of the c anister and the electri c conector c ommanding the draining
valve are disconnected;
The sleeve for fixing the dra ining valve is taken off and the valve is taken apart .
The carbon canister is taken apart .
REMOUNTING
Perform in the reverse orde r the dismounting opera tions.
14 - 3
PETROL VAPOURS-ASPIRATION
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E7J-A-2/60 ENGINE17
IGNITION AND INJECTION
17 - 11
The catalyst efficiency is maximal when the air e xcess value (l ) is within the limits l =
0,97 ...1,03.
The i njection c omputer is adopting the adjustment strategy of the fuel m ixture enriching
in order to observe the a.m. condition. In order to inform the computer about the enriching
degree of t he mixture, the oxygen sensor is used, which is sending an electric signal of a
value oscillating between 150 and 800 mV. When the engine is warm and operating in the « closed loop « stage, the tension generated
by the oxygen sensor must quickly oscillate between 150 +/- 50 m V, corresponding to the
poor mixture and 750+/- 50 mV corresponding to the enriched mixture. The maximal-minimal
range must be as large as possible (at least 500 mV), confirming the sensor good operation.
The correction of the m ixture enri ching may be seen by means of t he CLIP tester, in t he
menu “FUNCTIONS TEST”, sub-menu “ENRICHING ADJUSTMENT” by the parameter
PR 035= enriching corre ction value.
The corre ction value has as limits 0 and 255, the avera ge value being placed at 128.
The interpretation of the parameter PRO 35 value, is the following :
- when it is gre ater than 128 the computer is requesting the mixture enriching- so, the
mixture has been poor.
- when it is smaller than 128, the computer is requesting the mixture penury- so, the
mixture has been ri ch. The en tra nce i n the enri ching adjustment is effective aft er a timing, due to water
temperature greater than 10 C when the acceleration t hrottle i s free ( idling e ngine) and t he
oxygen sensor is enough warm ( over 350 C). Until the moment of e nteri ng in this stage,
the enri ching correction value (PRO 53) will be 128. In the enri ching stage, the injection c omputer will not take i nto a ccount t he va lues
furnished by the oxygen sensor, in the fol lowing situations :
- accelera tion pushed at maximum
-sudden accelera tion
- at decelerating, with free accelera tion pedal inform ation.
- in case of a damaged oxygen sensor.
“DEGENERATED” OPERATION WAY IN CASE OF THE OXYGEN SENSOR DAMAGE
When the tension furnished by the oxygen sensor is not correct ( is changing a little bit
or not at all ), during enri ching adjustment, t he computer will not pass to t he »degenera ted »
operation way unl ess the damage ha s been re cognized a s being present for at least 10
minutes. Only in this case, the damage will be memori zed.
When a damage at the oxygen sensor is detected and if the damage has been already memorized,
then it will pass directly to the « open loop » operation (enriching correction = 128).
ADJUSTMENT OF THE FUEL
MIXTURE ENRICHING
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E7J-A-2/60 ENGINE17
IGNITION AND INJECTION
17 - 16
S
TEPS IN DIAGNOSING
INSPECTION OF DEFECTS
This stage is the indispensable start ing-point before any intervention on the car. if the
defect is indicated by the t ester, then remedy it; if no defe ct ha s been signalled by t he
tester, a conformity inspection will ha ve to be made, thus helping t o spot the possible
causes. To do that check on the fol lowing elements:
- the electric circuit corre sponding to the defect which has been signalled;
- the electric connectors along the circuit (oxidized spots, deform ed plugs, etc.);
- the e lectric re sistance that is not i n keeping with the element connected to that
electric circ uit; - the state of the plugs (cut or worn-out insulation, areas with traces of pressing, etc.).
CONFORMITY I NSPECTION
Its aim is to check on the various states and parameters, to detect some anomaly when
the tester failed to find defe cts.
This phase allows:- to diagnose a breakdown or failure without displaying the defe ct corre sponding to
a deficient functioning of the parts or following complaints from the user. - to check the good functioning of the injection system and to ensure no breakdown
or failure will appear immediately aft er the repair ha s been made.
So, this heading concerns a diagnosing of the various states and parameters, unde r
certain inspection conditions.
If a state is defective or a parameter is be yond tolerance, the corre sponding diagnose
page will have to be consulted.
LOCALIZING A DEFECT AFTER USER’S COMPLAINT
If after the inspection of the injection system by means of the CLIP tester (inspection of
defects and i nspection of conform ity) the cause of the user’s c omplaint ha s not be en e limi-
nated, then the logical schema of finding out of the possible causes of the problem will be
used. These schemas will only be used under the following circumstances:- no defect has been shown by the tester;
- no anomaly has been signalled by the inspection of conformity;
- the car does not work properly. DIAGNOSING-INTRODUCTION
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E7J-A-2/60 ENGINE17
IGNITION AND INJECTION
17 - 29
DIAG
NOSING-INTERPRETING THE DEFECTS
DEF ECT
PRE SEN TOR
MEMORIZEDINFORMATION ROTATION SENSOR
1. Faulty cogs of the engine flywheel
2. Absence of flywheel signal.
In orde r to do this type of diagnosing, the sensor for atmospheric pressure
mu st not be faulty
Conditions of breakdown detection by the calculator:
-the contact is taken and the dialogue with the calculator is waited for to
be lo st, then the dialogue with the calculator is re-entered and the memo-
rized defec ts are erased
-opera te the starter for 10 seconds or start the engine and keep it in idle
m ode.
Condition of performing the diagnosing:
-defec t is present
-the defect has been memorized but is recorded in the “present” state.
Check the connection and the state of the rotation sensor
Change the connector if necessary.
Check the resistance of rotation sensor.
Remedy rotation sensor if necessary.
Connect the 90-way terminal-tester instead of the calculator and check the insulation, the
continuity and the absence of contact resistance along the circuits:
pin 54 of calculator
♦ pin A of rotation sensor
pin 24 of calculator
♦ pin B of ro tation sensor.
Remedy if necessary.
Check the condition of the cogs of the engine flywheel.
Change the rotation sensor if the incident persists.
The proble m is not yet solved! Consequently, the injection calculator must be changed.
CAUTION! The destruction of the calculator has probably been caused by an electric shock.
The cause of the destruction must be found before mounting a new
calcul ator.
Er ase defects memorized by the computer.
Perform the steps under “Suggestions” to confirm the repair.
Remedy other possible defects.
AFTER
R EPAIR
12.
SUGGESTIONS
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IGNITION AND INJECTION
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DIAG
NOSING-INTERPRETING THE DEFECTS
DEFECT
PRESENTOR
MEMORI ZEDOXYGEN PROBE CIRCUIT
Breakdown of oxygen probe signal
Conditions of breakdown detection by the calculator:
-se t the contact
-start the engine and wait for the enrichment adjustment to be
active for at least 5 minutes.
Conditions of performing the diagnosing:
-defec t is present
-t he de fe ct ha s bee n memoriz ed but is recorded in the “present” stat e .
SUGGESTIONS
Check the connection and the condition of the oxygen probe
Change the connector if necessary.
Check if there is any “false air” caused by cases of lack of watertightness along the
exhau st-probe circuit.
If the ca r has been running a lot out of town proceed to probe-cleaning
Check, after setting the contact, the presence of +12 V at pin A of the oxygen probe.
Remedy if necessary
Connect the 90-way terminal-tester instead of the calculator and check the insulation,
the continuity and the absence of contact resistance along the circuits:
pin 45 of calculator
♦ pin C of ox ygen probe
pin 80 of calculator
♦ pin D of oxygen probe.
Remedy if necessary.
Change the oxygen probe if the incident persists
Th e pr ob lem is not yet solved! Consequently, the injection calculator must be changed.
CAUTION! The destruction of the calculator has probably been caused by an electric shock.
The cause of the destruction must be found before mounting a new
calcul ator.
Er ase defects memorized by the computer.
Perform the steps under “Suggestions” to confirm the repair.
Remedy other possible defects.
AFTER REPA IR
21.
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E7J-A-2/60 ENGINE17
IGNITION AND INJECTION
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DIAG
NOSING-INTERPRETING THE DEFECTS
DETONATION SENSOR CIRCUIT
Breakdown of detonation signalDEFECT
PR ESENT OR
MEMORI ZED23.
Condition of breakdown detection by the calculator:
-do a route-test, with the engine heated and under high rotation
ra tio.
Condition of performing the diagnosing:
-the defe ct is present
-the defect has been memorized but is re corded in the “present” state.
SUGGESTIONS
Check the connection and the condition of the detonation sensor
Change the connector if necessary.
Check the mounting of the detonation sensor on the engine block.
Tighten to the couple the detonation sensor.
Connect the 90-way terminal-tester instead of the calculator and check the insulation,
the continuity and the absence of contact resistance along the circuits:
pin 20 of calculator -> pin 1 of detonation sensor
pin 79 of calculator -> pin 2 of detonation sensor
pin 79 of calculator -> detonation sensor screening.
Remedy if necessary.
If the incident persists, change the detonation sensor.
Th e pr ob lem is not yet solved! Consequently, the injection calculator must be changed.
CAUTION! The destruction of the calculator has probably been caused by an electric shock.
The cause of the destruction must be found before mounting a new
calcul ator.
Erase defects memorized by the computer.
Perform the steps under “Suggestions” to confirm the repair.
Remedy other possible defects.AFTER
REPAIR
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E7J-A-2/60 ENGINE17
IGNITION AND INJECTION
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DIAGNOSING-CON
FORMITY TEST
SUGGESTIONS B - Wi
th the hot engine, in idle mode, wit hout consumers
Battery voltage
LIST OF STÃTES
State: +After Contact to calc u-
lator
Parameter: Supply voltage of
calc ulator
If the parameter: Supply volt-
age of calc ulator
Th en the parameter: Engine
rotation ratio Confirmed state
13V
750
l
ems arise, refer
to the diagnosing
of that param-
eter
Petrol pump com-
m and
State: Co mmand of actuators’
relay
Confi rmed state
Confi rmed state
Stat e: Petrol pump relay com-
m and
Co mmand of ac-
tuat ors
If furthe r prob-
l ems arise, refer
to the diagnos-
ing of the rota-
tion signal infor-
mation defectConfi rmed stateStat e: Ro tation signal
Ro tation signal
If further
proble ms arise,
refer to the
“Diagnosing Conditions”
Confi rmed stateSt ate: Recognition of the 1
cylinder
Recognition of the
1 cylinder
1.
2.
3.
4.
5. Heating of oxygen
probe Stat
e: Heating of oxygen
probe
Confi rmed state
Cl apper potenti-
ometer Stat
e: Pos ition of clapper of
acceleration pedal: free (raise d)Confi rmed stateIf further
problems arise,
refer to the
di agnosing of
that parameter
Stat e: Idle mode adjustment
Parameter: engine rotation
Parameter: To lerance of idle
m ode regimen
Parameter: Idle mode RCO
Parameter: Idle mode RCO
adapta tion.Confi rmed state
725 < X < 7 75 rot/min
-25 < X < +25 ro t/min
5 % < X < 12 %
-3 % < X < 7 % If furthe
r prob-
l ems arise, refer
to the diagnos-
ing of that state
Idle mode adjust-
m
ent
6.
7.
8.
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IGNITION AND INJECTION
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DIAG
NOSING-INTERPRETING THE STATES
PARAM ETERDETONATION SIGNAL
SUGGESTIONSNo defect should be present or memorized
The de tonation sensor should generate a signal, the amplitude of which must differ from 0,
a proof of the fact that it perceives the mechanical vibrations of the engine.
If th e signal = 0:
- check if the sensor is well fixed
- ch eck the insulation and continuity of cabling along the circuits:
pin 20 of calculator
♦ pin 1 of detonation sensor
pin 79 of calculator
♦ pin 2 of detonation sensor
pin 19 of calculator
♦ pin 1 of detonation sensor screening.
Replace detonation sensor if necessary.
AFTER REPAIR
PA R A M E T E RADAPTATION OF ENRICHMENT WHILE RUNNING
ADAPTATION OF ENRICHMENT IN IDLE MODE
SUGGESTIONS No defect should be present or memorized.
Do initialization.
Ma
ke sure the canister draining valve is watertight.
Erase memo ry o f th e injection calculator.
With the engine hot, in the stage of the idle mode adjustment, watch these parameters and
notice:
- if one of the parameters drifts to the MAX limit, then there is no enough petrol
- if one of the parameters drifts to the MIN limit, then there is too much petrol.
Ensure the cleanness and the good functioning of:
- p etrol filter
- petr ol pump
- petrol supply circuit
- petr ol tank.
AFTER REPAIR Perform again the conformity test.
Perform again the conformity test
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