S02 ENGINE KNOCK / CYCLICAL WHEN WARM - Alfa - 166 - eLearn

3308709 - S02 ENGINE KNOCK / CYCLICAL WHEN WARM

The engine is making a cyclical noise, noticeable when the engine is hot during brisk acceleration and using long ratios

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	Check the type of fuelPreliminarily check that there is no water or other fluids in the fuel tank	Continue to Step 1	Presence of dirt in the fuel tank	Clean the fuel tank Op. 1040A24
		Continue to Step 1	Fuel unsuitable	Clean the fuel tank Op. 1040A24 and fill with suitable fuel
1	TYPE OF NOISE CHECK	All OK	Problems met	Operation
	Carry out a road test and check whether the noise sounds metallic during brisk acceleration and using long ratios	Metallic sound: Continue to Step 2	Duller sound: probably knocking	Overhaul the engine: check the condition of the main bearings and replace them: Op. 1024A10
2	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Connect diagnostic equipment (Examiner or other instruments) to the diagnostic socket. Verify: that there are no faults in the engine management control unit the plausibility of all the parameters	Continue to Step 3	An error is detected in the control unit	Continue following the instructions for the diagnostic equipment
		Continue to Step 3	Lack of dialogue with the control unit	Restore the connection between the engine management control unit and the diagnostic connector ( See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT ).
3	PISTON CROWN CHECK	All OK	Problems met	Operation
	Remove the cylinder head and check the condition of the piston crowns	Continue to Step 4	Deposits on the piston crowns	Remove the deposits or replace the pistons and connecting rods (see Assembly 1028H)
4	HECK ON CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis	Fault persists	Search for the fault starting from another symptom'