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DIESEL INJECTION
Fault finding – Test13B
13B -244V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
TEST2
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 applying test 10 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 TEST2.
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DIESEL INJECTION
Fault finding – Test13B
13B -258V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
TEST8
CONTINUED 1
CASE No. 3: If at least one of these values does not stabilise (20 seconds after starting)
–Check the low pressure circuit with test 2 Low pressure circuit check.
–Check the conformity of the fuel used, apply test 10 Diesel fuel conformity check.
–Apply Part B of this test to confirm the fault finding procedure
CASE No. 4: If the fuel flow correction values are all correct (between - 5 mg/st and + 5 mg/st)
Apply Part C of this test (Fuel return flow measurement).
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DIESEL INJECTION
Fault finding – Test13B
13B -262V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
2 - Checking the balance of the injector return flows:
3 - Removing the tool:
Disconnect the pipe from an injector:
–press on the injector clip,
–pull vertically on the end piece of the pipe of tool Mot.1760, placing a wipe on the end piece to prevent run-off.
Lift the end piece vertically so that the fuel contained in the pipes flows into the measuring cylinders of tool Mot.1760.
Remove the other 3 pipes using the same procedure.
TEST8
CONTINUED 5
Does the engine start? – Fit Mot. 1760 as shown in the tool fitting procedure.
–Start the vehicle or perform a 15 second starting sequence
(with ignition key).
–Measure the length travelled by the diesel fuel in the pipes of the
Mot. 1760.
–Replace the injector if the length travelled by the fuel is more than
10 cm compared with the average of the other three injectors. NO
YES
–The injector return pipes must be fitted to the injectors.
–Start the engine.
–Display the Fuel circuit sub-function in the CLIP diagnostic tool.
–Raise the temperature of the engine.
–Read the diesel fuel temperature with PR063 Fuel temperature until a diesel fuel temperature greater than
50˚C is reached
–Switch off the engine.
–Fit Mot. 1760 as shown in the installation procedure (see step 1).
–Check the value of the PR038 Rail pressure.
–Ask another Cotech to monitor the rise in fuel in the cans during engine turnover, as one of the cans will fill up
quickly if one of the injectors is leaking.
–Start the engine.
–Accelerate the engine until the pressure in the rail is 550 bar:
●if the engine speed is less than 3,000 rpm, maintain this pressure.
●if the engine speed is greater than 3000 rpm, reduce the engine speed until the rail pressure is 500 bar and
maintain this pressure.
–Maintain these conditions for one minute.
–Release the accelerator pedal and maintain the idle speed for 10 seconds.
–Switch off the engine.
–Measure the quantity of fuel contained in each measuring cylinder.
–Replace the injector if the quantity of fuel is more than 50 ml.
–Remove Mot. 1760 as shown in the tool removal procedure (see step 3).
IMPORTANT:
Use a cleaning cloth (part number 77 11 211 707) to absorb fuel run-off.
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DIESEL INJECTION
Fault finding – Test13B
13B -264V3 MR-372-J84-13B250$900.mif
TEST9 Air path around the turbocharger
Check for the air filter
Check the replacement frequency for the air filter in the Maintenance Booklet.
Compare the part numbers of the air filter fitted to the vehicle and that of the air filter recommended by the
manufacturer.
Check the air filter direction of fitting.
Is the air filter fitted to the vehicle correct?
YES NO
Check the condition of the air filter
Visually inspect the condition of the filter
section of the air filter.
Is either the air filter or its seal
damaged?
Is the air filter clogged (does it contain
a lot of impurities)?YESReplace the air filter (see MR 364
(Mégane II) or 370 (Scénic II),
Mechanical, 12A, Fuel mixture, Air
filter, Removal - Refitting).
NO
Low pressure circuit check
Note:
According to the vehicle type, maximum
visual access will either be from above or
from below.
Visually inspect the condition of the
following components:
–fresh air inlet scoop on the front end
panel of the vehicle,
–air filter air inlet pipe,
–filter air pipe up to the compressor
inlet,
–air flowmeter mountings.
Is one of these components incorrect
(disconnected, cut, bent, pierced or
kinked pipes)?YESReplace the defective parts (see MR 364
(Mégane II) or 370 (Scénic II),
Mechanical, 12B, Turbocharging).
EDC16
PROGRAM No.: C1
Vdiag No.: 51
EDC16_V51_TEST9
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DIESEL INJECTION
Fault finding – Test13B
13B -266V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
TEST10 Diesel fuel conformity check
WARNING
During t hisop eration, it is essential t o:
–refrain from smoking or bringing incandescent objects close to the work area,
–protect yourself against fuel splashes due to residual pressure in the pipes,
–wear safety goggles with side guards,
–wear leaktight gloves (Nitrile type).
IMPORTA NT
–To avoid any corrosion or damage, protect the areas on which fuel is likely to run.
–To prevent impurities from entering the circuit, place protective plugs on all fuel circuit components
exposed to the open air.
Preparations:
Weigh an empty 1300 ml plastic cup (part no. 77 11 171 413) with its cover (part no. 77 11 171 416) using
electronic scales such as those used in body paint workshops (example: PANDA part no. 77 11 224 995). Record
the weight of the empty plastic cup.
This type of plastic cup is used to prepare paint.
Remove 1 litre of fuel at the diesel filter outlet (see MR 364 (Mégane II) or MR 370 (Scénic II), Mechanical,
19C, Tank, Draining the fuel tank), using a pneumatic transfer pump (part no. 634-200) and place it in the
1300 ml plastic cup.
Cover the plastic cup with its cover and let it settle for approximately 2 minutes.
Is the fuel cloudy or does it
separate into two parts?YESThe diesel fuel contains water and is not compliant.
Drain the fuel circuit, including the tank (see MR 364
(Mégane II) or MR 370 (Scénic II), Mechanical, 19C,
Tank, Draining the fuel tank).
NO
EDC16_V51_TEST10
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DIESEL INJECTION
Fault finding – Test13B
13B -269V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
Part 1. Overpressure valve return flow test:
TEST11 Incorrect operation of the overpressure valve
Is the engine working?
–Fit Mot. 1760 as shown in the tool fitting procedure (see part 2).
–Press the Start button (with card).
–Measure the length travelled by the diesel fuel in the pipes of the Mot. 1760.
–Replace the overpressure valve if the diesel length travelled is greater than 10 cm.
–The overpressure valve fuel return pipe must be fitted to the injector rail.
–Start the engine.
–Set the Clip diagnostic tool to parameter reading mode.
–Raise the temperature of the engine.
–Display parameter PR063 Fuel temperature. Increase the diesel temperature to above 50˚C.
–Switch off the engine.
–Fit Mot. 1760 as shown in the tool fitting procedure (see part 2).
–View parameter PR038 Rail pressure.
–Ask another Cotech to monitor the rise in fuel in the container during engine turnover, as the container will fill up
quickly if the overpressure valve is leaking.
–Start the engine.
–Accelerate the engine until the pressure in the rail is 550 bar:
–if the engine speed is less than 3000 rpm, maintain this pressure,
–if the engine speed is greater than 3000 rpm, reduce the engine speed until the rail pressure is 500 bar
and maintain this pressure.
–Maintain these conditions for 1 min.
–Release the accelerator pedal and maintain the idle speed for 10 seconds.
–Switch off the engine.
–Measure the length of diesel contained in the measuring cylinder.
–Replace the injector rail if the quantity of diesel is greater than 5 ml.
–Remove Mot. 1760 as shown in the tool removal procedure (see part 3).
YESNO
EDC16_V51_TEST11
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DIESEL INJECTION
Fault finding – Test13B
13B -270V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
Part 2: Fitting the tool:
Remove the engine undertray.
Disconnect the overpressure valve fuel return pipe according to the following procedure (do not remove the clips):
–press the clip,
–pull vertically on the end piece (1) of the fuel return pipe.
TEST11
CONTINUED 1
IMPORTANT
The end piece is fragile. Be careful not to break it by pulling it too hard. Replace
Page 271 of 273
DIESEL INJECTION
Fault finding – Test13B
13B -271V3 MR-372-J84-13B250$900.mif
EDC16
PROGRAM No.: C1
Vdiag No.: 51
Fit blanking plugs (B), from the kit (part number 77 01 208 209), on the end pieces of the fuel return pipe. If Mot.
1760 is not fitted immediately on the overpressure valve, place a blanking plug (A) on the overpressure valve fuel
return opening.
Shown above is the pipe (Mot. 1760) with the end piece (2) on the right and the plug (4) on the left.
Remove the clip and the plug from the end piece (2) of the pipe of Mot. 1760, leave the plug (4) in place.
TEST11
CONTINUED 2