13B-11
MR-372-J84-13B200$108.mif
V13
13B
DIESEL INJECTION
Fault finding – System operation
System outline
The high pressure injection system is designed to deliver a precise quantity of diesel fuel to the engine at a set
moment.
It is fitted with a 112-track BOSCH EDC16 C3 type computer.
The system comprises:
– a priming bulb on the low pressure circuit,
– a diesel filter,
– a high pressure pump with a built-in low pressure pump (transfer pump),
– a high pressure regulator mounted on the pump,
– an injector rail,
– a diesel fuel pressure sensor built into the rail,
– four solenoid injectors,
– a coolant temperature sensor,
– a cylinder reference sensor,
– an engine speed sensor,
– a turbocharger pressure sensor,
– an accelerator pedal potentiometer,
– an EGR solenoid valve,
– an atmospheric pressure sensor integrated into the injection computer,
– an air flowmeter with an air temperature sensor,
– a turbocharging pressure limitation solenoid valve,
– a motorised damper valve,
– a particle filter,
– a particle filter differential pressure sensor,
– a particle filter upstream temperature sensor,
– a particle filter downstream temperature sensor,
– a temperature sensor upstream of the turbine,
– four thermoplungers
The common rail direct high pressure injection system works sequentially (based on the petrol engine multipoint
injection).
This injection system reduces operating noise, reduces the volume of pollutant gases and particles and produces
high engine torque at low engine speeds thanks to a pre-injection procedure.
The high pressure pump generates the high pressure and transmits it to the injector rail. The actuator located on the
pump controls the quantity of diesel fuel supplied, according to the requirement determined by the computer. The rail
supplies each injector through a steel pipe.
MR-372-J84-13B200$108.mif
EDC16
Program No: C1
Vdiag No: 18, 1C, 20,
50, 58, 5C
13B-325
MR-372-J84-13B200$828.mif
V13
EDC16
Program No.: C1
Vdiag no.: 18, 1C, 20,
50, 58, 5CDIESEL INJECTION
Fault finding – Fault Finding Chart13B
ALP 6 Fuel system leaks
NOTESBefore dealing with this customer complaint, check that there are no faults, and
the conformity (or otherwise) of the parameters and statuses using the
diagnostic tool.
If the customer complaint is not eliminated, perform the following checks.
IMPORTANT
Please observe the cleanliness guidelines and safety advice.
Procedure for checking for an external leak on the fuel circuit:
Clean away traces of grease with clean thinner and wipe the part or parts concerned with cleaning cloths.
Start the engine and increase the engine coolant temperature to 80°C.
Stop the engine and check for traces of grease on the part or parts concerned.
If this is the case, replace the part or parts concerned.
Bleed the fuel circuit and continue the checks.
Does the priming bulb show traces of grease? (Visual
and tactile inspections)
(If there is a priming bulb)
NO
Does the diesel filter show traces of grease?
(Visual and tactile inspections)
NO
Do the fuel return pipes show traces of grease?
(Visual and tactile inspections)
NO
YESCheck the assembly
of the components
and the condition of
the seal at the union
of the two
components, if the
leak is at the seal.
Replace the part or
the parts concerned.
Bleed the fuel circuit
and continue the
checks.
YES
YES
AFTER REPAIRCarry out a road test followed by a complete check with the diagnostic tool.
EDC16_V50_ALP6/EDC16_V58_ALP6/EDC16_V5C_ALP6/EDC16_V18_ALP6/EDC16_V1C_ALP6/EDC16_V20_ALP6
13B-344
MR-372-J84-13B200$900.mif
V13
DIESEL INJECTION
Fault finding – Tests
EDC16
Program No.: C1
Vdiag no.: 18, 1C, 20,
50, 58, 5C
13B
TEST 3
CONTINUED
Check the condition of the priming bulb, and that it is working properly.
Perform repairs if necessary and continue the test.
If the fault is still present with a low fuel level, check the consistency of the actual fuel level and that indicated on
the instrument panel.
– The transfer pump is supplied via a venturi valve located beneath it.
Check that the opening of the venturi (6 to 8 mm in diameter) is not blocked by dirt contained in the fuel tank.
Check the priming of the low pressure diesel circuit.
Check the conformity of the fuel used by running test 11 Diesel fuel conformity check.
If the diesel fuel is not correct:
– Replace the diesel fuel.
– Change the diesel filter.
– Bleed the low and high pressure diesel circuit.
Low pressure circuit correct.
END OF TEST3.
