22 · Diagnostics

Engine starts with difficulty

Make: Fiat
Model: Doblò Factory Service Manual
Year: 2000–2010
Section: Starting › Engine starts with difficulty

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Fault diagnosisEngine starts with difficulty

ENGINE STARTS WITH DIFFICULTY

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	First check: the state of the spark plugs and leads; that the air filter is not blocked; the condition of the air intake circuit	Continue to Step 1	Plugs worn	Replace the spark plugs Op. 5510D10
			Damaged leads	Replace the leads Op. 5510D14
			Component of air intake circuit damaged	Repair or replace the faulty component
			Air filter clogged	Replace the filter element Op. 1048A14
1	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket Verify: that there are no errors in the control unit the plausibiilty of the parameters	Continue to Step 2	Error detected in the control unit	Continue following the instructions given by the diagnostic equipment
		Continue to Step 2	Implausible parameters	Continue following the instructions given by the diagnostic equipment
2	CHECK ON PETROL VAPOUR RECOVERY SYSTEM	All OK	Problems met	Operation
	Check that the petrol vapour recovery system is working properly	Continue to Step 3	Air leaks	Renew the correct seal
			Engine oil vapour intake pipe broken	Replace the pipe Op. 1080D24
			Pipe from canister to solenoid broken	Replace the pipe Op. 1080E62
3	CHECKING DELIVERY PRESSURE	All OK	Problems met	Operation
	Check that the fuel pressure is correct Op. 0510C10	Continue to Step 4	Insufficient fuel pressure: pipe blocked	Eliminate the blockage; if necessary replace the pipes Op. 1040B34
			Fuel pressure insufficient: filter blocked	Replace pump assembly Op. 1040A70
			Insufficient fuel supply pressure: regulator stuck	Replace pump assembly Op. 1040A70
			Insufficient fuel pump: pump faulty	Replace pump assembly Op. 1040A70
4	CHECKING TIMING	All OK	Problems met	Operation
	Check that the timing is correct Op. 0510A20	Continue to Step 5	Timing incorrect	Restore the correct timing Op. 1032B10
1.2 8v Climatizzatore	Check that the timing is correct Op. 0510A20	Continue to Step 5	Timing incorrect	Restore the correct timing Op. 1032B14
5	CHECKING CYLINDER COMPRESSION	All OK	Problems met	Operation
	Carry out the cylinder compression test Op. 0510A10	Continue to Step 7	Insufficient cylinder compression	Continue to Step 6
6	CHECKING CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems met	Operation
	Carry out R/R on head to check the valve seal Check the condition of the cylinders/piston rings	Continue to Step 7	Insufficient valve seal	Overhaul the cylinder head Op. 1016E10
		Continue to Step 7	Cylinders/piston rings worn	Repair the leak
7	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis	Fault persists: control unit defective	Replace control unit Op. 1056B82

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	First check: that the air filter is not blocked; the condition of the air intake circuit Remove the spark plugs and check the condition of the spark plugs and make sure that the gap is correct	Continue to Step 1	Component of air intake circuit damaged	Repair or replace the faulty component
			Air filter clogged	Replace the filter Op. 1048A10
			Spark plugs damaged	Replace the spark plugs
			Spark plugs wet	Dry the spark plugs and proceed Continue to Step 1
1	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket. Verify: that there are no errors in the control unit the plausibiilty of the parameters	Continue to Step 2	Error detected in the control unit	Continue according to the instructions for the diagnostic equipment
		Continue to Step 2	Implausible parameters	Continue according to the instructions for the diagnostic equipment
2	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Carry out active diagnosis of canister solenoid	Continue to Step 3	Solenoid valve faulty	Replace the solenoid valve Op. 1080E28
3	CHECK ON PETROL VAPOUR RECOVERY SYSTEM	All OK	Problems met	Operation
	Check the petrol vapour recovery system seal	Continue to Step 4	Air leaks	Renew the correct seal
	Check the petrol vapour recovery system seal	Continue to Step 4	Pipes connected to supply broken	Replace the pipes Op. 1080E62
4	CHECKING DELIVERY PRESSURE	All OK	Problems met	Operation
	Check that the fuel pressure is correct Op. 0510C10	Continue to Step 5	Fuel pressure too low: supply pipe obstructed	Eliminate the blockage; if necessary replace the pipes
	Check that the fuel pressure is correct Op. 0510C10	Continue to Step 5	Insufficient fuel pump: pump faulty	Replace pump assembly Op. 1040A70
5	CHECKING TIMING	All OK	Problems met	Operation
	Check that the timing is correct Op. 0510A20	Continue to Step 6	Timing incorrect	Restore the correct timing Op. 1032B14
6	CHECKING CYLINDER COMPRESSION	All OK	Problems met	Operation
	Carry out the cylinder compression test Op. 0510A10	Continue to Step 8	Insufficient cylinder compression	Continue to Step 7
7	CHECKING CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems met	Operation
	Carry out R/R on head to check the valve seal Op. 1016C10 Check the condition of the cylinders/piston rings	Continue to Step 8	Insufficient valve seal	Overhaul the cylinder head Op. 1016E10
			Cylinders/piston rings worn	Repair the leak
			Faulty coupling between head/cylinder block-crankcase	Restore correct coupling
8	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis	Fault persists: control unit defective	Replace control unit Op. 1056B82 Search for the fault starting from another symptom'

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	Check, in order: that the heater plug warning light comes on and goes out once heating is completed; that the battery is charged; that the starter motor is working correctly; that the lubricating oil level is correct; Op. 0010T11 that the diesel pipes are not leaking the condition of the air intake circuit; that the air filter is not clogged	Continue to Step 1	After 10 seconds the plug warning light flashes for about 30 seconds	See table K45 HEATER PLUGS WARNING LIGHT NOT WORKING
			Battery discharged	Recharge the battery Op. 5530B14
			Battery discharged and no longer rechargeable	Replace the battery Op. 5530B10
			Starter motor faulty.	Replace the starter motor Op. 5520B10
			Low oil level	Restore the correct level Op. 0010T11
			Faults in the intake circuit	Restore correct operation
			Fuel leaks detected	Stop the leaks
			Air filter clogged	Replace the filter element Op. 1048A14
1.9 DIESEL Climatizzatore	Check, in order: that the heater plug warning light comes on and goes out once heating is completed; that the battery is charged; that the starter motor is working correctly; that the lubricating oil level is correct; Op. 0010T11 that the diesel pipes are not leaking the condition of the air intake circuit; that the air filter is not clogged	Continue to Step 1	After 10 seconds the plug warning light flashes for about 30 seconds	See table K45 HEATER PLUGS WARNING LIGHT NOT WORKING
			Battery discharged	Recharge the battery Op. 5530B14
			Battery discharged and no longer rechargeable	Replace the battery Op. 5530B10
			Starter motor faulty.	Replace the starter motor Op. 5520B12
			Low oil level	Restore the correct level Op. 0010T11
			Faults in the intake circuit	Restore correct operation
			Fuel leaks detected	Stop the leaks
			Air filter clogged	Replace the filter element Op. 1048A14
1	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket Verify: that there are no errors in the control unit the plausibiilty of the parameters	Continue to Step 2	Error detected in the control unit	Continue following the instructions given by the diagnostic equipment
		Continue to Step 2	Implausible parameters	Continue following the instructions given by the diagnostic equipment
2	CHECK FOR PRESENCE OF AIR	All OK	Problems met	Operation
	Check that there is no air in the fuel injection system	Continue to Step 3	Air present	Bleed the air
3	CHECK ON DIESEL FILTER	All OK	Problems met	Operation
	Check that the diesel filter is not clogged	Continue to Step 4	Diesel filter clogged	Replace the filter Op. 1044B10
4	CHECK ON FUEL INJECTION PUMP TIMING	All OK	Problems met	Operation
	Check the timing of the fuel injection pump Op. 1060A20	Continue to Step 5	Fuel injection pump timing incorrect	Restore the correct timing Op. 1060A20
5	CHECKING VALVE CLEARANCES	All OK	Problems met	Operation
	Check that the valve tappet clearance is correct. Op. 1036H14	Continue to Step 6	Valve clearance incorrect	Overhaul the cylinder head Op. 1036H10
6	CHECK ON EGR VALVE	All OK	Problems met	Operation
	Visually check the operation of the EGR valve, after dismantling it Op. 1080C10	Continue to Step 7	EGR valve jammed open	Replace the EGR valve Op. 1080C10
7	CHECK ON FUEL INJECTORS	All OK	Problems met	Operation
	Check the injectors for leaks and that they are correctly calibrated Op. 1060B10	Continue to Step 8	Fuel injectors calibrated incorrectly	Restore the correct calibration Op. 1060B10
		Continue to Step 8	Faulty injectors	Replace the injectors Op. 1060B10
8	CHECKING CYLINDER COMPRESSION	All OK	Problems met	Operation
	Carry out the cylinder compression test Op. 0510A10	Continue to Step 10	Insufficient cylinder compression	Continue to Step 9
9	CHECKING CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems met	Operation
	R/R cylinder head Op. 1016C10Check cylinder/piston ring conditions	Continue to Step 10	Insufficient valve seal	Overhaul the cylinder head Op. 1016E10
10	CHECK ON FUEL INJECTION PUMP	All OK	Problems met	Operation
	Check that the fuel injection pump is working correctly	Continue to Step 11	Pump faulty	Replace the pump Op. 1060A10
11	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Check that the fault is no longer present	End of diagnosis	The fault persists: control unit defective	Replace control unit Op. 1060D80

0	PRELIMINARY CHECKS	All OK	Problems met	Operation
		Results of the tests
	Check, in order: the condition of the air intake circuit whether the diesel pipes are leaking; the condition of the air filter; that there is no petrol, water, paraffin or dirt in the diesel filter.	Continue to Step 1	Faulty in the air intake circuit	Restore the air intake circuit
			Leaks from diesel pipes. Battery flat	Retighten the pipes, and if necessary replace them.
			Blocked filter	Replace the diesel filter Op. 1044B10
			Presence of water, petrol, paraffin or dirt detected	Clean the tank and pipes and replace the diesel filter Op. 1044B10
1	CHECKING WITH DIAGNOSTIC EQUIPMENT	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket. Verify: that there are no errors in the control unit the plausibiilty of the parameters	Continue to Step 2	Error detected in the control unit	Continue following the instructions for the diagnostic equipment
			Implausible parameters	Continue following the instructions for the diagnostic equipment
			Lack of dialogue with the control unit	Restore the connection between engine management control unit and diagnostic connector
2	HIGH PRESSURE CHECK	All OK	Problems met	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket. Check as described in test 1060D that the diesel pressure parameter is correct	Continue to Step 10	Pressure not correct	Continue to Step 3
3	CHECK RETURN LOW PRESSURE	All OK	Problems met	Operation
	Check as described in test 1060A that the pressure in the return pipe to the tank is below 1 bar.	Continue to Step 4	Pressure above maximum limit: return pipe to tank blocked	Repair the pipe; if necessary replace it
4	CHECK ON DELIVERY LOW PRESSURE	All OK	Problems met	Operation
	Check as described in test 1060B that the diesel pressure between filter and pressure pump is between 2 and 3 bar	Continue to Step 10	Pressure below minimum limit or above maximum limit	Continue to Step 5
5	CHECK ON DELIVERY LOW PRESSURE	All OK	Problems met	Operation
	Choke the return pipe from the pressure regulating valve and repeat test 1060B with the pipe choked, checking that the pressure at the filter outlet is below 2 bar	Continue to Step 6	Pressure rises to 5 bar: pressure regulating valve on filter mounting out of adjustment	Replace the valve Op. 1044B16
6	CHECK ON DELIVERY LOW PRESSURE	All OK	Problems met	Operation
	Check that the difference in pressure upstream and downstream of the filter is less than 1 bar	Continue to Step 7	Difference in pressure over 1 bar	Replace the diesel filter Op. 1044B10
7	CHECK ON DELIVERY LOW PRESSURE	All OK	Problems met	Operation
	Check that the pressure of the supply pump at the filter inlet is over 2.2 bar	Continue to Step 10	Pressure below 2 bar	Continue to Step 8
8	CHECK ON DELIVERY LOW PRESSURE	All OK	Problems met	Operation
	Measure the difference in pressure between electric pump outlet and filter inlet, checking that it is less than 0.3 bar	Continue to Step 9	Pressure difference greater than 0.3 bar	Replace the pipe
9	CHECK ON DELIVERY LOW PRESSURE	All OK	Problems met	Operation
	Check as described in test 1040AA that the pump's supply voltage is 12V and that the absorbed current is between 2 and 10 amps.	Continue to Step 10	Voltage < 12 V	Check electric wiring See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT
			Current > 10 amp: pump faulty	Replace fuel pump assembly Op. 1040A70
			Current > 10 amp: pump faulty	Current < 2 Amp.: pump blocked Op. 1040A70and clean fuel tank
10	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Replace the DRV high-pressure valve and check that the fault is no longer present	End of diagnosis	Fault persists	Continue to Step 1
11	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Replace the pressure pump and check that the fault is no longer present	End of diagnosis	Fault persists	Continue to Step 12
12	CHECKING CYLINDER COMPRESSION	All OK	Problems met	Operation
	Carry out the cylinder compression test	Continue to Step 14	Insufficient cylinder compression	Continue to Step 13
13	CHECKING CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems met	Operation
	Carry out R.R. on head to check the valve seal Check the condition of the cylinders/piston rings	Continue to Step 14	Insufficient valve seal	Overhaul the cylinder head Op. 1016E10
			Cylinders/piston rings worn	Repair the leak
			Faulty coupling between head/cylinder block-crankcase	Restore correct coupling
14	CHECKING CORRECT OPERATION	All OK	Problems met	Operation
	Replace the pressure pump and check that the fault is no longer present	End of diagnosis	Fault persists: control unit defective	Replace engine management control unit Op. 1060G80

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Parts & tools for this job Staging For 2000 Fiat Doblò

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