B20 ENGINE STARTS, AND CUTS OUT STRAIGHT AWAY - Alfa - 147 - eLearn

3022567 - B20 ENGINE STARTS, AND CUTS OUT STRAIGHT AWAY

The engine starts, with difficulty and then immediately cuts out suddenly

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	Check, in order: that there is no water, other fluids or dirt in the fuel filter that there is no water, other fluids or dirt in the fuel tank that there are no obstuctions in the catalyzer	Continue to Step 1	There is water, other fluids or dirt in the fuel filter	Replace the filter element
			There is water, other fluids or dirt in the fuel tank	Cleaning tank
			Catalyzer obstructed	Replace the catalyzer
1	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket Recreate the conditions in which the problem occurs and check: for errors in the control unit plausibility of all the parameters	Continue to Step 2	Errors detected in the control unit	Continue following the instructions for the diagnostic equipment
			unreliable parameters	Continue following the instructions for the diagnostic equipment
			Lack of dialogue with the control unit	Restore the correct connections
2	HIGH PRESSURE CHECK	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socketCheck as described in Test 1060D that the diesel pressure parameter is correct	Continue to Step 10	Pressure not correct	Continue to Step 3
3	CHECK ON RETURN LOW PRESSURE	All OK	Problems met	Operation
	Check that the pressure in the return pipe to the tank is less than 1 bar. See Test 1060A Low return fuel pressure circuit check	Continue to Step 4	Pressure above maximum limit (return pipe to tank blocked)	Repair the pipe; if necessary replace it.
4	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Check that the diesel pressure between filter and radial jet pump See Test 1060B Low fuel pressure supply circuit check is between 2 and 3 bar.	Continue to Step 10	Pressure below minimum limit or above maximum limit	Continue to Step 5
5	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Choke the return pipe downstream from the low-pressure regulating valve, checking that the pressure at the filter outlet remains below 2 bar See Test 1060B Low fuel pressure supply circuit check	Continue to Step 6	Pressure rises to 5 bar: blocked pressure regulation valve on filter support	Replace the valve Op. 1044B16
6	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 7	Difference in pressure over 1 bar	Replace the fuel filter cartridge Op. 1044B16
7	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Check that the pressure of the supply pump at the filter inlet is over 2.2 bar	Continue to Step 10	Pressure below 2.2 bar	Continue to Step 8
8	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Measure the difference in pressure between electric pump outlet and filter inlet and check that it is less than 0.3 bar	Continue to Step 9	Difference in pressure over 0.3 bar	Replace the pipe
9	LOW SUPPLY PRESSURE CHECK	All OK	Problems met	Operation
	Check that the pump supply voltage is 12 V and that the absorbed current is between 2 and 10 amp. See Test 1040AA Check supply voltage and absorption current	Continue to Step 10	Voltage below 12 V	Check wiring, intervention on connection cables See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT
			Current greater than 10 amp.: pump faulty	Replace the fuel pump assembly Op. 1040A70
			Current below 2 amp.: jet pump blocked	Replace fuel pump assembly Op. 1040A70 and clean the fuel tank
10	CHECK ON CORRECT OPERATION	All OK	Problems met	Operation
	Replace theDRV high-pressure regulating valve and check that the fault is no longer present.	End of diagnosis	Fault persists	Continue to Step 11
11	CHECK ON CORRECT OPERATION	All OK	Problems met	Operation
	Replace the pressure pump and check that the fault is no longer present	End of diagnosis	Fault persists: control unit faulty	Replace engine management control unit Op. 1060G80 Search for the fault starting from another symptom'