D01 ENGINE NOT RUNNING SMOOTHLY / (HESISTANT) - Alfa - 156 - eLearn

3233014 - D01 ENGINE NOT RUNNING SMOOTHLY / (HESISTANT)

There are decreases in performance, possibly prolonged, during acceleration

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	First check: whether there is service information on the subject the condition of the air intake circuit spark plugs	Continue to Step 1	Air intake circuit check	Restore correct operation of the intake circuit
		Continue to Step 1	Spark plugs not the type recommended by the manufacturer	Replace the spark plugs
1	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 the plausibiilty of the parameters	Continue to Step 2	There are errors	Continue following the instructions for the diagnostic equipment
		Continue to Step 2	Incoherent parameter	Continue following the instructions for the diagnostic equipment and analyse the factors that could cause these inconsistencies.
2	ROAD TEST WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Road test the vehicle, reproducing the conditions under which the fault arises, keeping the diagnostic equipment connected Check:: that there are no faults in the control unit the plausibiilty of the parameters, in particular: rail pressure - rail pressure setting air mass engine temperature upstream Lambda sensor voltage	Continue to Step 3	Error arises suddenly in the control unit	Continue following the instructions for the diagnostic equipment.
		Continue to Step 3	Incoherent parameter	Continue following the instructions for the diagnostic equipment and analyse the factors that could cause these inconsistencies.
3	LOW PRESSURE CIRCUIT CHECK	All OK	Problems met	Operation
	Check that the fuel pressure is correct	Continue to Step 4	Incorrect pressure: obstructions in the fuel delivery pipe	Remove the obstructions in the fuel pipe, and if necessary replace it
			Incorrect pressure: tank not sufficiently ventilated	Restore the tank ventilation Replace the spark plugs
			Pressure not correct: petrol pump damaged or not correctly supplied	Replace fuel pump assembly Op. 1040A70
4	RAIL PRESSURE SENSOR CHECK	All OK	Problems met	Operation
	Check the operation of the rail sensor	Continue to Step 5	Pressure sensor faulty	Replace sensor
5	PRESSURE REGULATOR CHECK	All OK	Problems met	Operation
	Check that the voltage regulator is working	Continue to Step 6	Pressure regulator faulty	Replace the pressure regulator
6	HIGH PRESSURE PUMP CHECK	All OK	Problems met	Operation
	Check the operation of the high pressure pump	Continue to Step 7	High pressure pump faulty	Replace high pressure pump
7	CHECK ON FUEL INJECTORS	All OK	Problems met	Operation
	Check the continuity/insulation of the injector wiring; in particular, make sure that the injector operating signal is present See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT	Continue to Step 8	No signal, wiring broken	Renew the wiring See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
		Continue to Step 8	No signal, wiring not broken	Replace engine management control unit
8	PHASE TRANSFORMER CHECK IN ACTIVE DIAGNOSIS	All OK	Problems met	Operation
	Check the operation of the phase transformer in active diagnosis	Continue to Step 9	Not working	Using a voltmeter (graphic is better) check the transformer operating signal and, if necessary, replace the transformer.
9	MODULAR MANIFOLD CHECK IN ACTIVE DIAGNOSIS	All OK	Problems met	Operation
	Check the operation of the modular manifold in active diagnosis	Continue to Step 10	Not working	Using a voltmeter (graphic is best) check the modular manifold operating signal and, if necessary, replace the modular manifold solenoid valve
10	IGNITION OPERATION CHECK	All OK	Problems met	Operation
	Check the continuity/insulation of the supply circuit and the coil operation; in particular, make sure that the coil operating signal is present See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT	Continue to Step 11	No supply/earth	Renew the wiring See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
		Continue to Step 11	No operating signal	Check the wiring between the coils and the ECU and, if necessary, replace the control unit See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
11	CHECKING TIMING	All OK	Problems met	Operation
	Check that the timing is correct	Continue to Step 12	Timing not correct	Ensure that the timing is correct
12	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis