D03 ENGINE NOT RUNNING SMOOTHLY / (IRREGULAR OPERATION) - Alfa - 147 - eLearn

3022581 - D03 ENGINE NOT RUNNING SMOOTHLY / (IRREGULAR OPERATION)

During driving, the engine misses and loses performance

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	Preliminarily check: the condition of the air filter the state of the spark plugs and leads; battery earth correctly fixed See E1010 SUPPLY	Continue to Step 1	Filter element dirty, damaged or incorrectly fitted	Replace or refit filter element correctly Op. 1048A14
			Spark plugs dirty or damaged	Replace the spark plugs Op. 5510D10
			Spark plug leads damaged	Replace the spark plug leads
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; plausibility of all the parameters	Continue to Step 2	'Supply system' error detected	See table Z50 MIXTURE STRENGTH ERROR
			'Misfire' error detected	See table Z56 UPSTREAM LAMBDA SENSOR SIGNAL ERROR
			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
2	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	'Supply system' error detected	See table Z50 MIXTURE STRENGTH ERROR
			'Misfire' error detected	See table Z56 UPSTREAM LAMBDA SENSOR SIGNAL ERROR
			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
3	CHECK ON FUEL PRESSURE	All OK	Problems met	Operation
	Check, if necessary on the road (to reproduce the conditions in which the fault arises), the fuel supply pressure Op. 0510C10	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. 1040A30
			Pressure not correct: tank insufficiently ventilated	Restsore the tank ventilation
			Pressure not correct: fuel pump electrical circuit broken	Repair fuel pump electrical circuit See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
			Pressure incorrect: fuel pump damaged	Replace fuel pump assembly Op. 1040A70
4	CHECK AIR CONDITIONING SYSTEM	All OK	Problems met	Operation
	Road test the vehicle and check whether the fault is affected by whether or not the air conditioner is switched on	Continue to Step 5	Fault present only with the air conditioner on	See table L10 CLIMATE CONTROL NOT COOLING
5	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'