D21 ENGINE CUTS OUT WHILST DRIVING - Alfa - GT - eLearn

125000499 - D21 ENGINE CUTS OUT WHILST DRIVING

The engine cuts out suddenly whilst driving. Later, after starting normally, it works again The engine cuts out suddenly whilst driving. Later, after starting normally, it works again

Results of the tests

PRELIMINARY CHECKS

All OK

Problems met

Operation

Preliminarily check:

that the earth is correctly fixed on the engine
that the battery earth is correctly fixed
correct fixing of the positive battery terminal and the leads connected to it
for any obstructions in the catalyzer
that there is no water or other fluids in the fuel tank

Continue to Step 1

Earth leads incorrectly fixed

Renew or, if necessary, replace the battery earth lead Op. Op. 5530B22 BATTERY EARTH LEAD - R+R

Battery positive earth incorrectly fixed

Restore battery positive lead Op. Op. 5530B26 LEAD BETWEEN BATTERY AND STARTER MOTOR - R+R

Catalytic converter or precatalyzers obstructed

Replace the exhaust manifold Op. Op. 1072C12 EXHAUST MANIFOLD - R R

Presence of dirt in the fuel tank

Clean the fuel tank

CHECKING WITH DIAGNOSTIC EQUIPMENT

All OK

Problems met

Operation

Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket.

Check:

that there are no faults in the engine management control unit;
plausibility of all the parameters

Continue to Step 2

Another error dectected in the control unit

Continue following the instructions for the diagnostic equipment

Inconsistent parameter

Continue following the instructions for the diagnostic equipment

ROAD TEST WITH DIAGNOSTIC EQUIPMENT

All OK

Problems met

Operation

Road test the vehicle, reproducing the conditions in which the fault arises, keeping the diagnostic equipment connected.

Check:

that there are no faults in the engine management control unit;
plausibility of all the parameters

Continue to Step 3

Error arises suddenly in the control unit

Continue following the instructions for the diagnostic equipment

Inconsistent parameter

Continue following the instructions for the diagnostic equipment

Loss of dialogue between the control unit and diagnostic instrument

Restore the control unit circuit supply See See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT

CHECK ON FUEL PRESSURE ON ROAD

All OK

Problems met

Operation

Road test the vehicle and check the fuel supply pressure Op. Op. 0510C10 FUEL SYSTEM - CHECK DELIVERY PRESSURE

Make sure that the conditions in which the problem occurs are reproduced

Continue to Step 4

Pressure not correct: obstructions in fuel delivery pipe

Remove the obstructions in the fuel pipe, and if necessary replace it Op. 1040B30

Pressure not correct: tank insufficiently ventilated

Restsore the tank ventilation

Pressure not correct: fuel pump electrical circuit broken

Repair fuel pump electrical circuit See See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT

Pressure incorrect: fuel pump damaged

Replace fuel pump assembly Op. Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R

CHECK ON CORRECT OPERATION

All OK

Problems met

Operation

Check that the fault is no longer present

Fault persists: control unit defective

Replace control unit Op. 1056B82 Search for the fault starting from another symptom''

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	Preliminarily check: That there is fuel in the tank; That the engine wiring is properly connected to earth; That the battery earth is correctly fixed; The correct fixing of positive battery terminal and that all leads are connected; that there is no water in the fuel filter	Continue to Step 1	No fuel	Introduce fuel
			Fastenings slack or oxidized	Re-attach correctly
			Presence of water in the fuel filter	Clean the tank and pipe and replace the filter element Op. Op. 1044B20 FUEL FILTER FILTERING ELEMENT - REPLACE
1	CHECK WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socketCheck that there are no errors in the control unit	Continue to Step 2	An error is detected in the control unit	Continue following the instructions for the diagnostic equipment
2	ROAD TEST WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Road test the vehicle, reproducting the conditions in which the fault arises, keeping the diagnostic socket connectedCheck that there are no errors stored in the control unit memory	Continue to Step 3	An error is detected in the control unit	Continue following the instructions for the diagnostic equipment
3	INJECTOR HIGH PRESSURE CHECK	All OK	Problems met	Operation
	Check, as described in the See Test See Test 1060C INJECTOR HIGH PRESSURE, FUEL CIRCUIT LEAKAGE TEST, that diesel leaks from the injector recirculation connections are small and about the same as one another.	Continue to Step 4	Consistent leak from one injector	Replace the injector Op. Op. 1060F10 FUEL INJECTORS
4	HIGH PRESSURE CHECK	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socketCheck as described in the See Test See Test 1060D ELECTRONIC DIESEL INJECTION CONTROLthat the diesel pressure parameter is correct	Continue to Step 12	Pressure not correct	Continue to Step 5
5	CHECK ON RETURN LOW PRESSURE	All OK	Problems met	Operation
	Check as described in the See Test See Test 1060A LOW RETURN FUEL PRESSURE CIRCUIT CHECKthat the pressure in the return pipe to the tank is under 1 bar	Continue to Step 6	Pressure above maximum limit: return pipe to tank blocked	Repair the pipe; if necessary replace it
6	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Check as described in the See Test See Test 1060B LOW FUEL PRESSURE SUPPLY CIRCUIT CHECKthat the diesel pressure between filter and pressure pump is between 2 and 3 bar	Continue to Step 12	Pressure below minimum limit or above maximum limit	Continue to Step 7
7	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Choke the return pipe from the pressure regulating valve and repeat the See Test See Test 1060B LOW FUEL PRESSURE SUPPLY CIRCUIT CHECKwith the pipe choked, checking that the pressure at the filter outlet is below 2 bar	Continue to Step 8	Pressure rises to 5 bar: blocked pressure regulation valve on filter support	Replace the valve Op. Op. 1044B16 DELIVERY ADJUSTMENT VALVE - R R
8	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Check that the difference in pressure upstream and downstream of the filter is less than 1 bar	Continue to Step 9	Difference in pressure greater than 1 bar	Replace the diesel filter cartridge Op. Op. 1044B20 FUEL FILTER FILTERING ELEMENT - REPLACE
9	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Check that the supply pump pressure at the filter inlet is over 2.2 bar	Continue to Step 12	Pressure below 2.2 bar	Continue to Step 10
10	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Measure the difference in pressure between electric pump outlet and filter inlet, checking that it is less than 0.3 bar	Continue to Step 11	Difference in pressure greater than 0.3 bar	Replace the pipe
11	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Check as described in the that the pump''s supply voltage is 12V and that the absorbed current is between 2 and 10 amps.	Continue to Step 12	Voltage < 12 V	Check electric wiring See See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT
			Current > 10 Amp: pump defective	Replace the fuel pump assembly Op. Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R
			Current < 2 Amp.: pump blocked	Replace fuel pump assembly Op. Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + Rand clean the fuel tank
12	CORRECT OPERATION CHECK	All OK	Problems met	Operation
	Replace the DRV pressure regulator and check that the fault is no longer present	End of diagnosis	Fault persists	Continue to Step 13
13	CORRECT OPERATION CHECK	All OK	Problems met	Operation
	Replace the pressure pump and check that the fault is no longer present	End of diagnosis	Fault persists	Contact Technical Service for further information on the problem