22 · Diagnostics

Engine idle irregular

Make: Lancia
Model: Thesis Factory Service Manual
Year: 2002–2009
Section: Engine › Engine idle irregular

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Fault diagnosisEngine idle irregular

ENGINE IDLE IRREGULAR

2.4 JTD 10V

STEP	OPERATIONS TO BE CARRIED OUT	TEST RESULTS
0	PRELIMINARY CHECKS	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check: condition of the air intake circuit; condition of the air filter and correct operation	Move on to Step	1. Fault in the air intake circuit	1. Renew the air intake circuit
		Move on to Step	2. Air filter blocked	2. Replace the filter element See in Op. 1048A14 air cleaner filtering element - replace.
1	CHECK USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket.Check: no errors in control unit parameter plausibility carry out the active diagnosis of the E.G.R. solenoid valve	Move on to Step	1. Error detected in the control unit	1. Continue following the instructions for the diagnostic equipment
			2. Parameters not plausible	2. Continue following the instructions for the diagnostic equipment
			3. No communication with the control unit	3. Restore the connection between the engine management control unit and the diagnostic connector (Wiring Diagram ) E5050 DIESEL ENGINE ELECTRONIC MANAGEMENT
			4. Solenoid valve not working	4. Check the continuity of the wiring < R1 > if necessary, replace the solenoid valve < R2 > See in Op. 1080C74 E.G.R. VALVE - R.R.
2	FUEL FILTER CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check fuel filter operation	Move on to Step	Water, petrol, paraffin or dirt found to be present	Clean the tank and ipes and replace the diesel filter cartridge See in Op. 1044B20 fuel filter filtering element - replace
3	VALVE CLEARANCE CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the tappet clearance is correct	Move on to Step	Valve clearance not correct	Adjust the tappets See in Op. 1036H10 CHECK AND ADJUST VALVE TAPPETS
4	CYLINDER COMPRESSION CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Carry out the cylinder compression check	Move on to Step	Cylinder compression insufficient	Move on to Step
5	CHECK THE CAUSE OF THE INSUFFICIENT COMPRESSION	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	R.R. the head to check the valve seal and check the condition of the cylinders/piston rings	Move on to Step	Valve seal insufficient	Overhaul the cylinder head See in Op. 1016E10 SINGLE CYLINDER HEAD, removed - Overhaul
6	CHECK ON CORRECT OPERATION	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the fault is no longer present		Fault persists control unit defective	Replace the engine management control unit See in Op. 1060G80 Diesel electronic injection system CONTROL UNIT - R.R.

2.0 TB, 2.4 20V, 3.0 V6

STEP	OPERATIONS TO BE CARRIED OUT	TEST RESULTS
0	PRELIMINARY CHECKS	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	First, check: condition of the air filter; the condition of the air intake circuit	Move on to Step	1. Air filter blocked	1. Replace the filter element See in Op. 1048A14 air cleaner filtering element - replace.
		Move on to Step	2. Fault in the air intake circuit	2. Restore the correct operation of the intake circuit
1	CHECK USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the diagnostic test equipment (Examiner or other instruments) to the tester input.Check: that there are no faults in the engine management control unit; parameter plausibility	Move on to Step	1. "Fuel system" error detected	1. Continue following the instructions in Table Z050
			2. Another error detected in the control unit	2. Continue following the instructions for the diagnostic equipment
			3. Parameter not consistent	3. Continue following the instructions for the diagnostic equipment
2	PETROL VAPOUR RECOVERY SYSTEM CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the condition and the seal of the pipe between the canister solenoid valve and the intake manifold		1. Air leaks	1. Restore the correct seal
			2. Pipe between solenoid valve and manifold damaged	2. Replace the pipe
3	PETROL VAPOUR RECOVERY SOLENOID VALVE CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Carry out the active diagnosis of the solenoid valve	Move on to Step	Solenoid valve not working	Move on to Step
4	SOLENOID VALVE ELECTRICAL CIRCUIT CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the petrol vapour recovery solenoid valve supply and earth (Wiring Diagram ) E5030 PETROL ENGINE ELECTRONIC MANAGEMENT	Move on to Step	1. Solenoid valve faulty	1. Replace the solenoid valve See in Op. 1080E28 enablement solenoid for flow of fuel vapours to inlet - r+r
		Move on to Step	2. Connections not correct	2. Repair the connections (Wiring Diagram ) E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
5	BRAKE SERVO AND PIPE CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the condition of the brake servo vacuum pipes;Check the operation of the single-acting valve and the brake servo Continue following the instructions in the test 3330DA Brake servo operational check	Move on to Step	1. Brake servo pipe defective	1. Replace the pipe
		Move on to Step	2. Brake servo defective	2. Replace the brake servo/pump assembly
6	FUEL PRESSURE CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
2.4 20 V,2.0 TB	Check the fuel supply pressure See in Op. 0510C10 FUEL SYSTEM - Check DELIVERY PRESSURE	Move on to Step	1. Fuel pressure too low: pipe obstructed	1. Eliminate the obstructions, if necessary, replace the pipe
2.4 20 V,2.0 TB		Move on to Step	2. Fuel pressure too low: pump defective	2. Replace the pump assembly See in Op. 1040A70 SUBMERGED PUMP ASSEMBLY complete with level gauge - R.R.
6	FUEL PRESSURE CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the fuel supply pressure See in Op. 0510C10 FUEL SYSTEM - Check DELIVERY PRESSURE	Move on to Step	1. Fuel pressure too low: pipe obstructed	1. Eliminate the obstructions, if necessary, replace the pipe
		Move on to Step	2. Fuel pressure too low: pump defective	2. Replace the pump assembly See in Op. 1040A70 SUBMERGED PUMP ASSEMBLY complete with level gauge - R.R.
7	PHASE TRANSFORMER SOLENOID VALVE CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
2.4 20 V,2.0 TB	Carry out the active diagnosis of the phase transformer solenoid valve	Move on to Step	Solenoid valve not working	Move on to Step
8	PHASE TRANSFORMER ELECTRICAL CIRCUIT CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
2.4 20 V,2.0 TB	Check the supply and earth for the phase transformer solenoid valve (Wiring Diagram ) E5030 PETROL ENGINE ELECTRONIC MANAGEMENT	Move on to Step	Connections not correct	Repair the connections (Wiring Diagram ) E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
9	PHASE TRANSFORMER CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
2.4 20 V,2.0 TB	Check the operation of the phase transformer supplying the phase transformer solenoid avlve directly.The engine speed should vary considerably (very irregular idling)	Move on to Step	There are no speed variations: phase transformer stuck	Replace the phase transformer See in Op. 1036C40 VARIABLE VALVE TIMING on inlet camshaft in cylinder head - R and R with shaft removed
10	TIMING CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the valve gear timing is correct	Move on to Step	Valve gear timing not correct	Restore the correct valve gear timing
11	CHECK ON CORRECT OPERATION	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the fault is no longer present		Fault persists control unit defective	Replace the control unit See in Op. 1056B82 Injection/ignition system CONTROL UNIT (one) - R.R.

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Parts & tools for this job For 2002 Lancia Thesis

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