D02 ENGINE NOT RUNNING SMOOTHLY / (LOSING POWER) - Alfa - GT - eLearn

125000494 - D02 ENGINE NOT RUNNING SMOOTHLY / (LOSING POWER)

Under conditions of constant load and speed, there are intermittent decreases in performance, even prolonged

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	Preliminarily check: the state of the spark plugs and leads; the condition of air filter the condition of the air intake circuit absence of obstructions in the catalytic converter	Continue to Step 1	Spark plugs dirty or damaged	Replace the spark plugs Op. Op. 5510D10 SPARK PLUGS - R+R
			Spark plug leads damaged	Replace the spark plug leads Op. 5510D14
			Air intake circuit fault	Eliminate the problem
			Catalyzer obstructed	Replace the exhaust manifold Op. Op. 1072C12 EXHAUST MANIFOLD - R R
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 See table Z50 MIXTURE STRENGTH ERROR
			''Misfire'' error detected	See table See table Z53 MISFIRE 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 See table Z50 MIXTURE STRENGTH ERROR
			''Misfire'' error detected	See table See table Z53 MISFIRE 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	FUEL PRESSURE ROAD TEST	All OK	Problems met	Operation
	Road test the vehicle and check the fuel supply pressure Op. Op. 0510C10 FUEL SYSTEM - CHECK DELIVERY PRESSUREin the conditions that lead to the anomaly	Continue to Step 4	Insufficient fuel pressure: pipes obstructed	Remove restrictions
			Insufficient fuel pressure: valve obstructed	Replace the tank cap Op. Op. 1040A40 PLUG FOR FUEL FILLER PIPE - R + R
			Insufficient fuel pressure: regulator out of calibration	Replace the pump assembly Op. Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R
			Low fuel pressure: defective pump	Replace the pump assembly Op. Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R
			Low fuel pressure: clogged filter	Replace the pump assembly Op. Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GUAGE CONTROL - R + R
4	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''