B13 ENGINE STARTS WITH DIFFICULTY' - Alfa - 147 - eLearn

3022566 - B13 ENGINE STARTS WITH DIFFICULTY'

The engine, especially when cold, starts with difficulty only after repeated attempts. When the key is turned, the instruments light up as normal, the starter motor turns, but the engine has difficulty in starting.

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	Check, in order: the condition of the air intake circuit seal of the diesel pipes; the condition of air filter that there is no petrol, water, paraffin or dirt in the diesel filter.	Continue to Step 1	Fault in air intake circuit	Repair the air intake circuit
			Leaks from the diesel pipes	Retighten the pipes, and if necessary replace them.
			Filter blocked	Replace the diesel filter cartridge Op. 1044B20
			Presence of water, petrol, paraffin or dirt detected	Clean the tank and pipes and replace the diesel filter cartridge Op. 1044B20
1	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket Check: for errors in the control unit plausibility of all the parameters	Continue to Step 2	An error is 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 connection between engine management control unit and diagnostic connector
2	HIGH PRESSURE CHECK	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socketCheck that the diesel pressure parameter is correct See Test 1060D Check high pressure fuel circuit	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 pressure pump is between 2 and 3 bar See Test 1060B Low fuel pressure supply circuit check	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 from the pressure regulating valve, making sure 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 PRESSUR 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 greater than 1 bar	Replace the diesel filter cartridge Op. 1044B20
7	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 10	Pressure below 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, checking that it is less than 0.3 bar	Continue to Step 9	Difference in pressure greater than 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 < 12 V	Check electric wiring See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT
			Current > 10 Amp: pump defective	Replace the fuel pump assembly Op. 1040A70
			Current < 2 Amp.: pump blocked	Replace the fuel pump assembly Op. 1040A70 and clean the fuel tank
10	CORRECT OPERATION CHECK	All OK	Problems met	Operation
	Replace the DRV high pressure valve and check that the fault is no longer present	End of diagnosis	Fault persists	Continue to Step 11
11	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	Continue to Step 12
12	CHECK ON CYLINDER COMPRESSION	All OK	Problems met	Operation
	Carry out the cylinder compression test	Continue to Step 13	Cylinder compression insufficient	Continue to Step 13
13	CHECK ON CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems met	Operation
	Carry out R.R. on head to check the valve sealCheck the condition of the cylinders/piston rings	Continue to Step 14	Insufficient valve seal	Overhaul the cylinder head Op. 1016E10
		Continue to Step 14	Cylinders/piston rings worn	Repair the leak
14	CHECK ON CORRECT OPERATION	All OK	Problems met	Operation
	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'