Engine does not produce best performance

Make: Fiat
Model: Grande Punto Factory Service Manual
Year: 2005–2012
Section: Engine › Engine does not produce best performance

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Fault diagnosisEngine does not produce best performance

ENGINE DOES NOT PRODUCE BEST PERFORMANCE

1.9 Multijet

The customer complains of: Reduced engine performance in all operating conditions

0	PRELIMINARY CHECKS	All OK	Problems encountered	Operation
		Test results
	Check that the engine oil level is correct Op. 0010T11 ENGINE OIL - CHECK LEVEL AND TOP UP, IF NECESSARY Check that the air intake/vacuum circuit is working properly by carrying out the See Test 1048OA AIR INTAKE/VACUUM CIRCUIT CHECK Check the condition of the fuel supply circuit and make sure that it is working properly See Test 1040OA FUEL SUPPLY CIRCUIT CHECK Check the operation of the low pressure supply circuit See Test 1060OB LOW FUEL DELIVERY PRESSURE CIRCUIT CHECK	Move on to Step 1	Oil level incorrect	Restore the correct engine oil level Op. 0010T11 ENGINE OIL - CHECK LEVEL AND TOP UP, IF NECESSARY
1	AMBIENT PARAMETERS CHECK	All OK	Problems encountered	Operation
	Select the following control unit at the diagnostic equipment: Electronic injection control unit EDC16C39 CF4/EOBD CAN (EP engine 1.9). Check the value of the following parameters: . Battery voltage See Test 5530BB BATTERY VOLTAGE CHECK . Accelerator pedal . Accelerator position 1 AD/C . Accelerator position 2 AD/C See Test 1068AC ACCELERATOR PEDAL CHECKS . Atmospheric pressure See Test 1060GD ATMOSPHERIC PRESSURE CHECK - Turbo pressure Target ?- Turbo pressure Measured See Test 1060GF SUPERCHARGING PRESSURE CHECK . Measured air mass See Test 1060GG CHECK MEASURED AIR MASS . Engine coolant temperature See Test 1060OE ENGINE COOLANT TEMPERATURE SENSOR OPERATION CHECK . Diesel temperature See Test 1060EA DIESEL TEMPERATURE CHECK - Target Diesel pressure - Measured Diesel pressure See Test 1060GH DIESEL PRESSURE CHECK . Engine rpm See Test 1060GI CHECK ENGINE SPEED	Move on to Step 2
2	ELECTRICAL EQUIPMENT CHECK	All OK	Problems encountered	Operation
	Check that fuse F59 has not blown (second from the left on the second row from the bottom)	Move on to Step 3	Fuse F59 has blown	Restore the connections or, if necessary, replace the junction unit in the engine compartment Op. 5505A13 ADDITIONAL JUNCTION UNIT IN ENGINE COMPARTMENT - R.R.
		Move on to Step 3	Fuse F20 has blown	Move on to Step 3
3	DIESEL PREHEATING RELAY CHECK	All OK	Problems encountered	Operation
	Check the diesel preheating relay circuit See Test 5505AC	Move on to Step 4
4	TURBOCHARGER ADJUSTMENT CHECK	All OK	Problems encountered	Operation
	Using the diagnostic equipment carry out the active diagnosis for the turbocharger regulating solenoid valve. Check the operation of the variable geometry control actuator	Move on to Step 5	Solenoid valve not working	Restore the wiring continuity See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT Replace the solenoid valve if necessary Op. 1064B42 SOLENOID CONTROLLING TURBOCHARGER VANE POSITION ACTUATOR - R.R
		Move on to Step 5	Actuator not working properly	Check the condition of the vacuum circuit, if necessary, replace the damaged components
5	CHECK USING DIAGNOSTIC EQUIPMENT	All OK	Problems encountered	Operation
	Carry out the active diagnosis for the E.G.R. solenoid valve	Move on to Step 6	E.G.R. solenoid valve not working	Restore the wiring continuity See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT Replace the solenoid valve if necessary Op. 1080C24 E.G.R. SYSTEM SOLENOID - R + R
6	BRAKE PEDAL SWITCH CHECK	All OK	Problems encountered	Operation
	Check that the brake pedal switch is working properly	Move on to Step 7	Brake pedal does not return	Eliminate the cause of the sticking
			Switch stuck closed	Replace the switch Op. 1060G38 BRAKE PEDAL SWITCH - R.R
			Wiring short circuited	Restore the correct connection See E2021 BRAKE LIGHTS
7	TURBOCHARGER CHECK	All OK	Problems encountered	Operation
	Check the operation of the turbocharger See Test 1064BA SUPERCHARGING PRESSURE CHECK	Move on to Step 8	Turbocharger faulty	Replace the turbocharger Op. 1064A27 TURBOCHARGER UNIT AND EXHAUST MANIFOLD - R.R.
8	HIGH PRESSURE CHECK	All OK	Problems encountered	Operation
	Connect the diagnotsic equipment to the diagnostic socket. Check that the diesel pressure parameter is correct See Test 1060OD HIGH PRESSURE FUEL CIRCUIT CHECK	Move on to Step 15	Pressure not correct	Move on to Step 9
9	LOW RETURN PRESSURE CHECK	All OK	Problems encountered	Operation
	that the pressure in the return pipe to the tank is less than 1 bar See Test 1060OA LOW FUEL RETURN PRESSURE CIRCUIT CHECK	Move on to Step 10	Pressure above the maximum limit: return pipe to the tank obstructed	Repair the pipe and replace if necessary.
10	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Check that the diesel pressure between the filter and the pressure pump is between 2 and 3 bar See Test 1060OB LOW FUEL DELIVERY PRESSURE CIRCUIT CHECK	Move on to Step 15	Pressure below the minimum limit or above the maximum value	Move on to Step 11
11	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Check that the difference in pressure upstream and downstream of the filter is less than 1 bar	Move on to Step 12	Difference in pressure more than 1 bar	Replace the fuel filter cartridge Op. 1044B10 FUEL FILTER ASSEMBLY - R + R OR REPLACE
12	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Check that the supply pump pressure at the filter inlet is more than 2.2 bar	Move on to Step 15	Pressure below 2 bar	Move on to Step 13
13	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Measure the difference in pressure between the electrical pump outlet and the filter inlet checking that it is less than 0.3 bar	Move on to Step 14	Difference in pressure more than 0.3 bar	Replace the pipe
14	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Check that the pump supply voltage is equal to 12V and that the current uptake is between 2 and 10 A See Test 1040AA CHECK ON SUPPLY VOLTAGE AND CURRENT UPTAKE	Move on to Step 15	Voltage lower than 12 V	Check electrical wiring See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT
			Current greater than 10 A: pump defective	Replace the fuel pump Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R
			Current less than 2 A: pump obstructed	Replace the fuel pump Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R and clean the fuel tank
15	CHECK CORRECT OPERATION	All OK	Problems encountered	Operation
	Replace the high pressure DRV valve Op. 1060E50 and check that the fault is no longer present	End of diagnosis	Fault persists	Move on to Step 16
16	CHECK ON CORRECT OPERATION	All OK	Problems encountered	Operation
	Replace the high pressure pump Op. 1060E10 DIESEL INJECTION PRESSURE PUMP - R.R. and check that the fault is no longer present	End of diagnosis	Fault persists	Move on to Step 17
17	TIMING CHECK	All OK	Problems encountered	Operation
	Check that the valve gear timing is correct	Move on to Step 18	Valve gear timing not correct	Restore the correct valve gear timing Op. 1032B10 TOOTHED TIMING BELT - R + R FOR TIMING ADJUSTMENT OR REPLACEMENT
18	VALVE CLEARANCE CHECK	All OK	Problems encountered	Operation
	Check that the tappet clearance is correct Op. 1036H10 VALVE TAPPETS - CHECK AND ADJUST CLEARANCE, IF NECESSARY	Move on to Step 19	Valve clearance not correct	Adjust the tappets
19	CYLINDER COMPRESSION CHECK	All OK	Problems encountered	Operation
	Carry out the cylinder compression check Op. 0510A10 CYLINDER COMPRESSION - CHECK FOR LOOSE SPARK PLUGS OR INJECTORS	Move on to Step 21	Cylinder compression insufficient	Move on to Step 20
20	CHECK ON CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems encountered	Operation
	Carry out Op. 1016C10 SINGLE CYLINDER HEAD - R.R. AND REPLACE GASKET to check the valve seal. Check condition of cylinders/piston rings	Move on to Step 21	Valve seal insufficient	Overhaul the head Op. 1016E10 SINGLE CYLINDER HEAD, REMOVED - OVERHAUL
		Move on to Step 21	Cylinders/piston rings worn	Restore the seal
21	CHECK ON CORRECT OPERATION	All OK	Problems encountered	Operation
	Check that the fault is no longer present	End of diagnosis	Fault persists	Replace the engine management control unit Op. 1060G80 DIESEL ELECTRONIC INJECTION CONTROL UNIT - .R

1.3 Multijet

The customer complains of: Reduced engine performance in all operating conditions

0	PRELIMINARY CHECKS	All OK	Problems encountered	Operation
		Test results
	Select the following control unit at the diagnostic equipment: Diesel Injection Marelli 6F3 EOBD CAN (EP 1.3 JTD). Check the value of the following parameters: . Battery voltage See Test 5530BB BATTERY VOLTAGE CHECK	Move on to Step 1
1	CONFIGURATION TESTS	All OK	Problems encountered	Operation
	Select the following control unit at the diagnostic equipment: Diesel Injection Marelli 6F3 EOBD CAN (EP 1.3 JTD engine). Check in the Configurations section whether the replacement of any of the following components was not followed by the subsequent configuration: - Injector In this case, carry out the configuration checking that the outcome is positive	Move on to Step 4	The outcome of the configuration is not positive	Move on to Step 2
2	ERRORS CHECK	All OK	Problems encountered	Operation
	Check whether any of the following errors are present using the diagnostic equipment: - P1301 - U0001 - U0426 - U1700	Move on to Step 4	1. Error P1301 is present 2. Error U0001 is present 3. Error U0426 is present 4. Error U1700 is present	1. Move on to Step 3 2. Continue as indicated See table U0001 CAN line error 3. Carry out the CODE programming. If this is not possible, replace the engine management control unit Op. 1060G80 DIESEL ELECTRONIC INJECTION CONTROL UNIT - .R 4. Continue as indicated See table U1700 CAN network (NCM - NBC)
3	IMA CLASSIFICATION	All OK	Problems encountered	Operation
	Carry out the IMA classification again on the diagnostic equipment in the Configurations section checking that the outcome is successful	End of diagnosis	The classification is not successful	Replace the engine management control unit Op. 1060G80 DIESEL ELECTRONIC INJECTION CONTROL UNIT - .R
4	PRELIMINARY CHECKS	All OK	Problems encountered	Operation
	Check that the air intake/vacuum circuit is working properly See Test 1048OA AIR INTAKE/VACUUM CIRCUIT CHECK Check the condition of the fuel supply circuit and make sure that it is working properly See Test 1040OA FUEL SUPPLY CIRCUIT CHECK	Move on to Step 5
5	AMBIENT PARAMETERS CHECK	All OK	Problems encountered	Operation
	Select the following control unit at the diagnostic equipment: Diesel Injection Marelli 6F3 EOBD CAN (EP 1.3 JTD engine). Check the value of the following parameters: - Accelerator position 1 AD/C - Accelerator position 2 AD/C See Test 1068AC ACCELERATOR PEDAL CHECKS - Coolant temperature See Test 1060OE ENGINE COOLANT TEMPERATURE SENSOR OPERATION CHECK - Diesel temperature See Test 1060EA DIESEL TEMPERATURE CHECK - Atmospheric pressure See Test 1060GD ATMOSPHERIC PRESSURE CHECK - Measured Diesel pressure See Test 1060GH DIESEL PRESSURE CHECK - Pressure regulator opening (MPROP) See Test 1060GR CHECK OPERATION OF FUEL PRESSURE SENSOR ON RAIL - Engine rpm See Test 1060GI CHECK ENGINE SPEED	Move on to Step 6
6	HIGH PRESSURE CHECK	All OK	Problems encountered	Operation
	Connect the diagnotsic equipment to the diagnostic socket. Check that the diesel pressure parameter is correct See Test 1060OD HIGH PRESSURE FUEL CIRCUIT CHECK	Move on to Step 12	Pressure not correct	Move on to Step 7
7	LOW RETURN PRESSURE CHECK	All OK	Problems encountered	Operation
	Check that the pressure in the return pipe to the tank is less than 1 bar See Test 1060OA LOW FUEL RETURN PRESSURE CIRCUIT CHECK	Move on to Step 8	Pressure above the maximum limit: return pipe to the tank obstructed	Repair the pipe and replace if necessary
8	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Check that the difference in pressure upstream and downstream of the filter is less than 1 bar	Move on to Step 9	Difference in pressure more than 1 bar	Replace the fuel filter cartridge Op. 1044B10 FUEL FILTER ASSEMBLY - R + R OR REPLACE
9	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Check that the pressure of the fuel pump at the filter inlet is more than 2.2 bar (75 CV) or 4.5 bar (90 CV)	Move on to Step 12	Pressure below 2 bar (75 CV) or 4.5 bar (90 CV)	Move on to Step 10
10	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Measure the difference in pressure between the electrical pump outlet and the filter inlet checking that it is less than 0.3 bar	Move on to Step 11	Difference in pressure more than 0.3 bar	Replace the pipe
11	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Check that the pump supply voltage is equal to 12V and that the current uptake is between 2 and 10 A See Test 1040AA CHECK ON SUPPLY VOLTAGE AND CURRENT UPTAKE	Move on to Step 12	1. Voltage lower than 12 V 2. Current greater than 10 A: pump defective 3. Current less than 2 A: pump obstructed	1. Check electrical wiring See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT 2. Replace the fuel pump Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R 3. Replace the fuel pump and clean the fuel tank Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R
12	CHECK ON CORRECT OPERATION	All OK	Problems encountered	Operation
	Replace the high pressure pump and check that the fault is no longer present Op. 1060E10 DIESEL INJECTION PRESSURE PUMP - R.R.	End of diagnosis	Fault persists	Move on to Step 13
13	CYLINDER COMPRESSION CHECK	All OK	Problems encountered	Operation
	Carry out the cylinder compression check Op. 0510A10 CYLINDER COMPRESSION - CHECK FOR LOOSE SPARK PLUGS OR INJECTORS	Move on to Step 15	Cylinder compression insufficient	Move on to Step 14
14	CHECK ON CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems encountered	Operation
	Check the valve seal. Op. 1016C10 SINGLE CYLINDER HEAD - R.R. AND REPLACE GASKET Check condition of cylinders/piston rings	Move on to Step 15	1. Valve seal insufficient 2. Cylinders/piston rings worn	1. Overhaul the head Op. 1016E10 SINGLE CYLINDER HEAD, REMOVED - OVERHAUL 2. Restore the seal
15	CHECK ON CORRECT OPERATION	All OK	Problems encountered	Operation
	Check that the fault is no longer present	End of diagnosis	Fault persists	Replace the engine management control unit Op. 1060G80 DIESEL ELECTRONIC INJECTION CONTROL UNIT - .R

1.2 8v, 1.4 8v

0	PRELIMINARY CHECKS	All OK	Problems encountered	Operation
		Test results
	First, check: - condition of the air filter; - the condition of the air intake circuit; - that there are no obstructions in the exhaust pipe	Move on to Step 1	Air intake circuit faulty	Eliminate the problem, if necessary, replace the filter element Op. 1048A14 AIR CLEANER FILTER ELEMENT - REPLACE.
		Move on to Step 1	Pipe obstructed	Restore the operation of the exhaust pipes
1	CHECK USING DIAGNOSTIC EQUIPMENT	All OK	Problems encountered	Operation
	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 2	Error detected in the control unit	Continue following the instructions for the diagnostic equipment
		Move on to Step 2	Parameter not consistent	Continue following the instructions for the diagnostic equipment
2	ROAD TEST USING DIAGNOSTIC EQUIPMENT	All OK	Problems encountered	Operation
	Carry out a road test keeping the diagnostic equipment connected. Check: - that there are no faults in the engine management control unit; - parameter plausibility	Move on to Step 3	The sudden onset of another error is detected	Continue following the instructions for the diagnostic equipment
		Move on to Step 3	Parameters not consistent	Continue following the instructions for the diagnostic equipment
3	FUEL PRESSURE ROAD TEST	All OK	Problems encountered	Operation
	Carry out a road test and check the fuel supply pressure Op. 0510C10 FUEL SYSTEM - CHECK DELIVERY PRESSURE under the conditions in which the fault occurs	Move on to Step 4	Fuel pressure too low: pipes obstructed	Eliminate the constrictions
		Move on to Step 4	Fuel pressure too low: pump defective	Replace the fuel pump assembly Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R
4	TIMING CHECK	All OK	Problems encountered	Operation
	Check that the valve gear timing is correct Op. 0510A20 TIMING GEAR WITH BELT DRIVE - CHECK - CARRY OUT OPERATION WITH CAM COVER(S) REMOVED AND TAPPETS ADJUSTED AND CRANKSHAFT PULLEY DETACHED (IF NECESSARY)	Move on to Step 5	Valve gear timing not correct	Restore the correct valve gear timing
5	CYLINDER COMPRESSION CHECK	All OK	Problems encountered	Operation
	Carry out the cylinder compression check Op. 0510A10 CYLINDER COMPRESSION - CHECK FOR LOOSE SPARK PLUGS OR INJECTORS	Move on to Step 7	Cylinder compression insufficient	Move on to Step 6
6	CHECK ON CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems encountered	Operation
	R.R. the head to check the valve seal. Check the condition of the cylinders/piston rings	Move on to Step 7	Valve seal insufficient	Overhaul the head
		Move on to Step 7	Cylinders/piston rings worn	Restore the seal
7	CHECK ON CORRECT OPERATION	All OK	Problems encountered	Operation
	Check that the fault is no longer present	End of diagnosis	Fault persists: control unit defective	Replace the control unit Op. 1056B82 INJECTION/IGNITION SYSTEM E.C.U. (ONE) - R + R

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