Engine does not produce best performance

Make: Fiat
Model: Bravo Factory Service Manual
Year: 2007–2014
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

1.4 16v

0	PRELIMINARY CHECKS	All OK	Problems encountered	Operation
	First, check: - the 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	Obstruction in the air intake circuit	Eliminate the obstruction; if necessary, replace the filter element Op. 1048A14 AIR CLEANER FILTER ELEMENT - REPLACE.
			Air intake via the inlet manifold/throttle body seal	Restore the correct seal.
			Exhaust pipe blocked	Restore the operation of the exhaust pipe.
1		All OK	Problems encountered	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket and check: - no faults in the engine management control unit; - parameter plausibility	End of diagnosis	Error detected in the control unit	Continue following the instructions on the diagnostic equipment
		End of diagnosis	Parameter not consistent	Continue following the instructions on the diagnostic equipment
2		All OK	Problems encountered	Operation
	Check the fuel supply pressure Op. 0520G46 FUEL SYSTEM - CHECK SUPPLY PRESSURE USING THE EXAMINER	Move on to Step 3	Fuel pressure too low: pipes obstructed	Eliminate the constrictions
		Move on to Step 3	Fuel pressure too low: pump defective	Replace the pump assembly Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R
3	IGNITION SYSTEM CHECK	All OK	Problems encountered	Operation
	Inspect the spark plugs and check that they are working properly Check the operation of the ignition coils by carrying out See Test 5510CI IGNITION COIL OPERATION CHECK	Move on to Step 4	Spark plugs defective	Replace spark plugs Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R
		Move on to Step 4	Coil defective	Replace coils Op. 5510C14 IGNITION COIL/S - R.R.
4		All OK	Problems encountered	Operation
	Check the correct operation of the knock sensor by carrying out the See Test 5510CH Check on operation of knock sensor	Move on to Step 5	Connection defective	Restore correct connection.
			Wiring defective	Restore the correct wiring.
			Detonation sensor defective	Replace the knock sensor Op. 5510C42 DETONATION SENSOR (ONE) - R.R.
5	AIR PRESSURE SENSOR CHECK	All OK	Problems encountered	Operation
	- Check that the air pressure / temperature sensor is working properly - Check the continuity of the wiring between the sensor and the engine control unit See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT	Move on to Step 6	Sensor defective	Replace the sensor
		Move on to Step 6	Wiring broken	Restore wiring continuity
6	INJECTOR CHECK	All OK	Problems encountered	Operation
	Check that the injectors are operating correctly by carrying out See Test 1056BA Injector operation check Check that the injector needle seal is correct	Move on to Step 7	Injector stuck/incorrectly adjusted	Replace the injector Op. 1056B70 INJECTOR (ONE) - R + R WITH FUEL MANIFOLD PIPE REMOVED - INCLUDES SEAL REPLACEMNT
		Move on to Step 7	Connections not correct
7	ENGINE TEMPERATURE SENSOR CHECK	All OK	Problems encountered	Operation
	Check that the sensor operates correctly by carrying out See Test 1056BC Engine coolant temperature sensor operation check	Move on to Step 8	Temperature sensor defective	1.Replace sensor Op. 1056B50 ENGINE COOLANT TEMPERATURE SENSOR - R + R
		Move on to Step 8	Connections not correct	Restore the correct connections See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT
8	ACCELERATOR PEDAL CHECK	All OK	Problems encountered	Operation
	Check that the accelerator pedal is working correctly See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT	Move on to Step 9	Accelerator pedal potentiometer defective	Replace accelerator pedal [PR_1068A20] Op. 1068A20 ACCELERATOR PEDAL WITH BUILT-IN POTENTIOMETER - R.R
		Move on to Step 9	Connections not correct	Restore the correct connections See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT
9	MOTORIZED THROTTLE CHECK	All OK	Problems encountered	Operation
	Check that the motorized throttle is working properly, carrying out See Test 1056BW Check on the throttle body actuator operation See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT	Move on to Step 10	Motorized throttle defective	Replace the motorized throttle Op. 1056B14 THROTTLE CASE - R + R
		Move on to Step 10	Connections not correct	Restore the correct connections See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT
10	BRAKING SYSTEM CHECK	All OK	Problems encountered	Operation
	Check that the brakes do not offer resistance to the wheels	Move on to Step 11	Wheels braked
11		All OK	Problems encountered	Operation
	Carry out the cylinder compression check	Move on to Step 13	Cylinder compression insufficient
12	CHECK ON CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems encountered	Operation
	R.R. head 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 13	Valve seal insufficient	Overhaul the head Op. 1016E10 SINGLE CYLINDER HEAD, REMOVED - OVERHAUL
		Move on to Step 13	Cylinders/piston rings worn	Restore the correct seal.
13	ENGINE CONTROL UNIT CHECK	All OK	Problems encountered	Operation
	Check that the engine control unit is working properly	End of diagnosis	Engine management control unit defective	Replace the engine management control unit Op. 1056B82 INJECTION/IGNITION SYSTEM E.C.U. (ONE) - R + R

1.9 JTD 8v, 1.9 JTD 16v

The customer complains that: 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 carrying out the See Test 1040OA Fuel supply circuit check Check the operation of the low pressure supply circuit by carrying out the See Test 1060OB Low pressure fuel supply 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	MODE PARAMETERS CHECK	All OK	Problems encountered	Operation
	Select the following control unit at the diagnostic equipment: EDC16C39 Diesel electronic injection control unit. 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 · Supercharging pressure Objective · Supercharging pressure Measured See Test 1060GF TURBOCHARGING PRESSURE CHECK · Measured air mass · Air temperature in the intake manifold See Test 1064BD SUPERCHARGING TEMPERATURE CHECK · Engine coolant temperature See Test 5030AA COOLANT TEMPERATURE SENSOR CHECK · Diesel temperature · Target Diesel pressure · Measured Diesel pressure See Test 1060GH DIESEL PRESSURE CHECK · Engine rpm	Move on to Step 2
2	TURBOCHARGER ADJUSTMENT CHECK	All OK	Problems encountered	Operation
	Using the diagnostic equipment, carry out the active diagnosis for the turbocharger regulating solenoid. Check the operation of the variable geometry control actuator by carrying out the See Test 1064BC VARIABLE GEOMETRY TURBOCHARGER ACTUATOR LEAKAGE TEST	Move on to Step 3	Solenoid not working	Restore the wiring continuity See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT Replace the solenoid if necessary Op. 1064B42 SOLENOID CONTROLLING TURBOCHARGER VANE POSITION ACTUATOR - R.R
		Move on to Step 3	Actuator not working properly	Check the condition of the vacuum circuit, if necessary, replace the damaged components
3	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 4	E.G.R. solenoid not working	Restore the wiring continuity See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT Replace the solenoid if necessary Op. 1080C24 E.G.R. SYSTEM SOLENOID - R + R
4	BRAKE PEDAL SWITCH CHECK	All OK	Problems encountered	Operation
	Check that the brake pedal switch is working properly	Move on to Step 5	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
5	TURBOCHARGER CHECK	All OK	Problems encountered	Operation
	Check as described in the See Test 1064BA TURBOCHARGING PRESSURE CHECK the operation of the turbocharger	Move on to Step 6	Turbocharger faulty	Replace the turbocharger Op. 1064A27 PIPE BETWEEN VACUUM RESERVOIR AND ACTUATOR CONTROL SOLENOID VALVE - R.R.
6	HIGH PRESSURE CHECK	All OK	Problems encountered	Operation
	Connect the diagnostic equipment to the diagnostic socket. Check as described in the See Test 1060OD Injector high pressure fuel circuit check that the diesel pressure parameter is correct	Move on to Step 7	Pressure not correct	Move on to Step 13
7	LOW RETURN PRESSURE CHECK	All OK	Problems encountered	Operation
	Check as described in the See Test 1060OA Low pressure fuel return circuit check that the pressure in the return pipe to the tank is less than 1 bar	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 as described in the See Test 1060OB Low pressure fuel supply circuit check that the diesel pressure between the filter and the pressure pump is between 2 and 3 bar	Move on to Step 10	Pressure below the minimum limit or above the maximum value	Move on to Step 9
9	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Check by carrying out the See Test that the difference in pressure upstream and downstream of the filter is less than 0.5 bar	Move on to Step 11	Difference in pressure more than 0.5 bar	Replace the fuel filter Op. 1044B10 FUEL FILTER ASSEMBLY - R + R OR REPLACE
10	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 12	Pressure below 2 bar	Move on to Step 11
11	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 13	Difference in pressure more than 0.3 bar	Replace the pipe
12	LOW SUPPLY PRESSURE CHECK	All OK	Problems encountered	Operation
	Check as described in the See Test 1040AA CHECK ON SUPPLY VOLTAGE AND CURRENT UPTAKE that the pump supply voltage is equal to 12V and that the current uptake is between 2 and 10 A	Move on to Step 13	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
13	CORRECT OPERATION CHECK	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 14
14	TIMING CHECK	All OK	Problems encountered	Operation
	Check that the timing system timing is correct	Move on to Step 15	Timing system timing not correct	Restore the correct timing system timing
15	CYLINDER COMPRESSION CHECK	All OK	Problems encountered	Operation
	Carry out the cylinder compression check Op. 0520G15 COMPRESSION TEST - CHECK WITH EXAMINER WITH SPARK PLUGS/INJECTORS REMOVED	Move on to Step 17	Cylinder compression insufficient	Move on to Step 16
16	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 17	Valve seal insufficient	Overhaul the head Op. 1016E10 SINGLE CYLINDER HEAD, REMOVED - OVERHAUL
		Move on to Step 17	Cylinders/piston rings worn	Restore the correct seal
17	CORRECT OPERATION CHECK	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.R

1.4 16v TJet

0	PRELIMINARY CHECKS	All OK	Problems encountered	Operation
	First, check: - the 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	Obstruction in the air intake circuit	Eliminate the obstruction; if necessary, replace the filter element Op. 1048A14 AIR CLEANER FILTER ELEMENT - REPLACE.
			Air intake via the inlet manifold/throttle body seal	Restore the correct seal.
			Exhaust pipe blocked	Restore the operation of the exhaust pipe.
1	CHECK USING DIAGNOSTIC EQUIPMENT	All OK	Problems encountered	Operation
	Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket and check: - no faults in the engine management control unit; - parameter plausibility	End of diagnosis	Error detected in the control unit	Continue following the instructions on the diagnostic equipment
		End of diagnosis	Parameter not consistent	Continue following the instructions on the diagnostic equipment
2	SUPERCHARGING SYSTEM CHECK	All OK	Problems encountered	Operation
	Check the supercharging system by carrying out the See Test 1064BB SUPERCHARGING PRESSURE SOLENOID (PIERBURG) VALVE OPERATION CHECK See Test 1064BF WASTE GATE VALVE PRESSURE CHECK See Test 1064BG CHECK ON CORRECT WASTE GATE VALVE ACTUATOR TRAVEL	Move on to Step 3	Turbo solenoid valve defective	Replace the solenoid Op. 1064B38 WASTE GATE SUPERCHARGING PRESSURE ADJUSTMENT SOLENOID VALVE - R.R.
			Signal at turbo solenoid valve does not conform	Restore the correct signal.
			Turbocharger defective	Change the turbocharger Op. 1064A27 PIPE BETWEEN VACUUM RESERVOIR AND ACTUATOR CONTROL SOLENOID VALVE - R.R. after having established the cause of the defect
			Waste-gate valve stuck	Change the turbocharger Op. 1064A27 PIPE BETWEEN VACUUM RESERVOIR AND ACTUATOR CONTROL SOLENOID VALVE - R.R.
3	FUEL PRESSURE TEST	All OK	Problems encountered	Operation
	Check the fuel supply pressure by carrying out See Test 1056BI FUEL SYSTEM RETURN PRESSURE CHECK See Test 1056BY FUEL SYSTEM SUPPLY PRESSURE CHECK	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 pump assembly Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R
4	IGNITION SYSTEM CHECK	All OK	Problems encountered	Operation
	Inspect the spark plugs and check that they are working properly. Check the operation of the ignition coils by carrying out See Test 5510CI IGNITION COIL OPERATION CHECK See Test 5510CE IGNITION CONTROL SIGNAL CHECK	Move on to Step 5	Spark plugs defective	Replace spark plugs Op. 5510D10 SPARK PLUGS - R+R
		Move on to Step 5	Coil defective	Replace coils Op. 5510C14 IGNITION COIL/S - R.R.
5	KNOCK SENSOR CHECK	All OK	Problems encountered	Operation
	Check the detonation sensor is working properly using the Examiner	Move on to Step 6	Connection defective	Restore correct connection.
			Wiring defective	Restore the correct wiring.
			Detonation sensor defective	Replace the knock sensor Op. 5510C42 DETONATION SENSOR (ONE) - R.R.
6	AIR PRESSURE SENSOR CHECK	All OK	Problems encountered	Operation
	- Check that the air pressure/temperature sensor is working properly by carrying out the See Test 1056BU CHECK ON OPERATION OF PRESSURE SENSOR AND/OR INTAKE AIR TEMPERATURE SENSOR Check the continuity of the wiring between the sensor and the engine control unit See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT	Move on to Step 7	Sensor defective	Replace the pressure sensor
		Move on to Step 7	Wiring broken	Restore wiring continuity
7	INJECTOR CHECK	All OK	Problems encountered	Operation
	Check that the injectors are operating correctly by carrying out See Test 1056BA Injector operation check Check that the injector needle seal is correct	Move on to Step 8	Injector stuck/incorrectly adjusted	Replace the injector Op. 1056B70 INJECTOR (ONE) - R + R WITH FUEL MANIFOLD PIPE REMOVED - INCLUDES SEAL REPLACEMNT
		Move on to Step 8	Connections not correct	Restore the correct connections See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT
8	CHECKING THE ENGINE COOLANT TEMPERATURE SENSOR	All OK	Problems encountered	Operation
	Check that the sensor operates correctly by carrying out See Test 1056BC Engine coolant temperature sensor operation check	Move on to Step 9	Temperature sensor defective	Replace the sensor Op. 1056B50 ENGINE COOLANT TEMPERATURE SENSOR - R + R
		Move on to Step 9	Connections not correct	Restore the correct connections See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT
9	ACCELERATOR PEDAL CHECK	All OK	Problems encountered	Operation
	Check that the accelerator pedal is working correctly See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT	Move on to Step 10	Accelerator pedal potentiometer defective	Replace the accelerator pedal Op. 1068A20 ACCELERATOR PEDAL WITH BUILT-IN POTENTIOMETER - R.R
		Move on to Step 10	Connections not correct	Restore the correct connections See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT
10	MOTORIZED THROTTLE CHECK	All OK	Problems encountered	Operation
	Check that the motorized throttle is working properly, carrying out See Test 1056BW Check on the throttle body actuator operation	Move on to Step 11	Motorized throttle defective	Replace the motorized throttle Op. 1056B14 THROTTLE CASE - R + R
		Move on to Step 11	Connections not correct	Restore the correct connections See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT
11	BRAKING SYSTEM CHECK	All OK	Problems encountered	Operation
	Check that the brakes do not offer resistance to the wheels	Move on to Step 12	Wheels braked	Restore the correct operation of the braking system.
12	CYLINDER COMPRESSION CHECK	All OK	Problems encountered	Operation
	Carry out the cylinder compression check Op. 0520G15 COMPRESSION TEST - CHECK WITH EXAMINER WITH SPARK PLUGS/INJECTORS REMOVED	Move on to Step 14	Cylinder compression insufficient	Move on to Step 13
13	CHECK ON CAUSE OF INSUFFICIENT COMPRESSION	All OK	Problems encountered	Operation
	R.R. head 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 14	Valve seal insufficient	Overhaul the head Op. 1016E10 SINGLE CYLINDER HEAD, REMOVED - OVERHAUL
		Move on to Step 14	Cylinders/piston rings worn	Restore the correct seal.
14	ENGINE CONTROL UNIT CHECK	All OK	Problems encountered	Operation
	Check that the engine control unit is working properly	End of diagnosis	Engine management control unit defective	Replace the engine management control unit Op. 1056B82 INJECTION/IGNITION SYSTEM E.C.U. (ONE) - R + R

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Parts & tools for this job For 2007 Fiat Bravo

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