FIAT / DUCATO 244eLearn workshop manual · English · Offline edition
Fault diagnosis

D10 ENGINE IDLE IRREGULAR

Engines: 2.0 16V, 2.0 JTD 8V, 2.3 JTD 16V, 2.8 JTD 8V
Engines: All listed engines
Engine idles unevenly. In particular, level is not consistent and regular when load is altered (e.g. activation of appliances etc.)
Engines: All listed engines
STEPOPERATIONS TO BE CARRIED OUTTEST RESULTS
0PRELIMINARY CHECKSALL OKPROBLEMS ENCOUNTEREDACTION
Check the condition of the air intake circuitCheck condition of the air filter and ensure it is working properlyMove on to Step 1Fault in the air intake circuitRenew the air intake circuit
Filter blockedReplace the filter element Op. 1048A14 AIR CLEANER FILTERING ELEMENT - REPLACE.
1CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Connect the diagnostic equipment to the diagnostic socket.Check:
  • that there are no errors in the control unit;
  • parameter plausibility
Move on to Step 2Error detected in the control unitContinue following the instructions for the diagnostic equipment
Parameters not plausibleContinue following the instructions for the diagnostic equipment
No communication with the control unitRestore the connection between the engine management control unit and the diagnostic connector See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT
2FUEL FILTER CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check fuel filter operationMove on to Step 3Water, petrol, paraffin or dirt found to be presentClean the tank and pipes and replace the filter element Op. 1044B20 FUEL FILTER FILTERING ELEMENT - REPLACE
3INJECTOR CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check for diesel leaks from the injectors See Test 1060O DIESEL FUEL INJECTION SUPPLY TESTSMove on to Step 4One or more injectors found to be leakingChange the injectors Op. 1060F10 FUEL INJECTORS
4EGR VALVE CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check EGR valve operation following removalMove on to Step 5EGR valve blocked openReplace the EGR valve Op. 1080C10 E.G.R. VALVE - R + R
5VALVE CLEARANCE CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check that the tappet clearance is correct Op. 1036H14 VALVE TAPPETS - CHECK CLEARANCEMove on to Step 6Valve clearance not correctReplace tappets Op. 1036H10 VALVE TAPPETS - CHECK AND ADJUST CLEARANCE
6CYLINDER COMPRESSION CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Carry out the cylinder compression checkMove on to Step 8Cylinder compression insufficientMove on to Step 7
7CHECK ON CAUSE OF INSUFFICIENT COMPRESSIONALL OKPROBLEMS ENCOUNTEREDACTION
R/R head for valve leakage test. Op. 1016C10 SINGLE CYLINDER HEAD, REMOVED - OVERHAULCheck condition of cylinders/piston ringsMove on to Step 8Valve seal insufficientOverhaul the head Op. 1016E10 SINGLE CYLINDER HEAD, REMOVED - OVERHAUL
8CHECK ON CORRECT OPERATIONALL OKPROBLEMS ENCOUNTEREDACTION
Check that the fault is no longer presentEnd of diagnosisFault persists: control unit defectiveReplace the engine management control unit Op. 1060G80 DS ELECTRIC INJECTION CONTROL UNIT - R R
Engines: All listed engines
Equipment / version codes: BIPOWER [200]
Engine idles unevenly. In particular, level is not consistent and regular when load is altered (e.g. activation of appliances etc.)
Engines: All listed engines
Equipment / version codes: BIPOWER [200]
STEPOPERATIONS TO BE CARRIED OUTTEST RESULTS
0PRELIMINARY CHECKSALL OKPROBLEMS ENCOUNTEREDACTION
First, check:
  • the condition of the air intake circuit;
  • condition of the air filter;
  • status of spark plugs and leads;
  • correct valve tappet clearance
Move on to Step 1Air intake circuit component damagedReplace damaged component
Filter element dirty or damagedReplace the filter element Op. 1048A14 AIR CLEANER FILTERING ELEMENT - REPLACE.
Spark plugs dirty or damagedClean or replace the spark plugs
Spark plug leads damagedReplace spark plug leads
Valve clearance not correctRestore correct valve clearance
1CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Connect the diagnostic equipment to the diagnostic connector and check the following at the engine management control unit:in error mode:
  • no faults in the petrol engine management control unit;
  • no faults in the methane engine management control unit;
in parameters ambient:
  • the plausibility of all the parameters;
  • methane injector diagnosis
Move on to Step 2Error detected in the control unitContinue following the instructions for the diagnostic equipment
Parameters not plausibleContinue following the instructions for the diagnostic equipment
Injector defectiveReplace the injector Op. 1058A70 INJECTOR(1) OF CNG INJECTION SYSTEM - R RWITH CNG MANIFOLD PIPE REMOVED INCLUDES GASKET REPLACEMENT
2CHECK PRESSURE CIRCUIT SEALALL OKPROBLEMS ENCOUNTEREDACTION
Check seal of high and low pressure system by carrying out Test 1058C See Test 1058O CNG SUPPLY TESTSMove on to Step 3System not sealedRestore seal
3CHECK IDLE ACTUATOR USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment connected to the diagnostic connector check the following at the petrol engine control unit, in the active diagnosis ambient:
  • correct operation of idle actuator
Move on to Step 4Idle actuator defectiveReplace idle actuator
Idle actuator rod contact seat dirtyClean idle actuator rod contact seat
Actuator connection not correctRestore correct connection between idle actuator and engine control unit See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
4CHECK METHANE PRESSUREALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment connected to the diagnostic connector check the following at the methane engine management control unit, in the parameters ambient:
  • the correct pressure in the methane circuit by carrying out Test 1058OA and Test 1044EB
See Test 1058O CNG SUPPLY TESTS See Test 1044E GAS PRESSURE CONTROL DEVICE
Move on to Step 5Pressure incorrect: methane pressure reduction unit defectiveReplace methane pressure reduction unit Op. 1044E10 CNG INJECTION SYSTEM PRESSURE REDUCTION UNIT - R R
Pressure not correct: methane pressure sensor blockedReplace methane pressure reduction unit Op. 1044E10 CNG INJECTION SYSTEM PRESSURE REDUCTION UNIT - R R
Pressure not correct: methane leaks from systemEliminate leaks from methane system
5CHECK METHANE INJECTORSALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment connected to the diagnostic connector check the following at the methane engine management control unit, in the active diagnosis ambient:
  • correct operation of methane injectors.
Check correct injector seal by carrying out Test 1058OB See Test 1058O CNG SUPPLY TESTS
Move on to Step 6Methane injector defectiveReplace the injector Op. 1058A70 INJECTOR(1) OF CNG INJECTION SYSTEM - R RWITH CNG MANIFOLD PIPE REMOVED INCLUDES GASKET REPLACEMENT
Petrol injectors permanently openReplace the injectors
6TIMING CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check that the valve gear timing is correctEnd of diagnosisValve gear timing not correctRestore the correct valve gear timing
Engines: All listed engines
Equipment / version codes: GPL [B73]
Engine idles unevenly. In particular, level is not consistent and regular when load is altered (e.g. activation of appliances etc.)
Engines: All listed engines
Equipment / version codes: GPL [B73]
STEPOPERATIONS TO BE CARRIED OUTTEST RESULTS
0PRELIMINARY CHECKSALL OKPROBLEMS ENCOUNTEREDACTION
First, check:
  • the condition of the air intake circuit;
  • condition and cleanliness of air filter;
  • correct status of spark plugs and leads;
  • correct valve tappet clearance.
If repairs are carried out to the flywheel or the rpm sensor or after the petrol engine management control unit has been replaced, check that:
  • the diagnostic equipment has been used to zero the self-adjustment parameters for restoring the control unit maps
Move on to Step 1Air intake circuit component damagedReplace damaged component
Filter element dirty or damagedReplace the filter element Op. 1048A14 AIR CLEANER FILTERING ELEMENT - REPLACE.
Spark plugs dirty or damagedClean or replace the spark plugs
Spark plug leads damagedReplace spark plug leads
Valve clearance not correctRestore correct valve clearance Op. 1036H10 VALVE TAPPETS - CHECK AND ADJUST CLEARANCE
Self-adjustment parameters not zeroedCarry out zeroing
1CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Connect the diagnostic equipment to the diagnostic connector and check the following at the engine management control unit: in the errors ambient:
  • no faults in the petrol engine management control unit;
  • no faults in the LPG engine management control unit;
in parameters ambient:
  • the plausibility of all the parameters
Move on to Step 2Error detected in the control unitContinue following the instructions for the diagnostic equipment
Parameters not plausibleContinue following the instructions for the diagnostic equipment
No dialogue with the petrol control unitRestore the connection between the engine management control unit and the diagnostic connector See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
No dialogue with the LPG control unitRestore the connection between the engine management control unit and the diagnostic connector See E5031 LPG FUEL SYSTEM ELECTRONIC MANAGEMENT
2CHECK IDLE ACTUATOR USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment connected to the diagnostic connector check the following at the petrol engine control unit, in the active diagnosis ambient:
  • correct operation of idle actuator
Move on to Step 3Idle actuator defectiveReplace idle actuator
Idle actuator rod contact seat dirtyClean idle actuator rod contact seat
Actuator connection not correctRestore correct connection between idle actuator and engine control unit See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT
3LPG INJECTOR CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment connected to the diagnostic connector check the following at the LPG engine management control unit, in the active diagnosis ambient:
  • the correct operation of the LPG injectors.
Check that the injectors are not leaking See Test 1057B GPL MULTIPOINT INJECTION FUEL SYSTEM
Move on to Step 4LPG injector defectiveReplace the injector
4RETURN SOLENOID VALVE EFFICIENCY CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment connected to the diagnostic connector check the following at the LPG engine management control unit, in the active diagnosis ambient:
  • the correct operation of the return solenoid valve.
Check the electrical operation of LPG return solenoid valve See Test 1043B GPL FUEL CIRCUIT PIPES
Move on to Step 5Solenoid defectiveReplace the solenoid valve
5CHECK LPG PRESSUREALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment connected to the diagnostic connector check the following at the LPG engine management control unit, in the parameters ambient and with the engine running:
  • the correct LPG pressure
Move on to Step 6Pressure not correct: multivalve calibrated port defectiveReplace multivalve
Pressure not correct: LPG pressure sensor blockedReplace LPG pressure sensor
Pressure not correct: LPG leaks from systemEliminate leaks from the LPG system
6CHECK LPG PUMP EFFICIENCYALL OKPROBLEMS ENCOUNTEREDACTION
Keeping the diagnostic equipment connected to the diagnostic connector check the following at the LPG engine management control unit, in the active diagnosis ambient:
  • correct operation of the LPG pump
Check the operation of the LPG warning light See Test 1043A GPL TANK
Move on to Step 7Irregular absorption by the LPG pumpReplace the LPG pump
Wiring defectiveRestore wiring See E5031 LPG FUEL SYSTEM ELECTRONIC MANAGEMENT
7TIMING CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check that the valve gear timing is correctEnd of diagnosisValve gear timing not correctRestore the correct valve gear timing Op. 1032B14 TOOTHED TIMING BELT - R + R FOR TIMING ADJUSTMENT OR REPLACEMENT VERSIONS WITH AIR CONDITIONER
Engines: All listed engines
Engine idles unevenly. In particular, level is not consistent and regular when load is altered (e.g. activation of appliances etc.)
Engines: All listed engines
STEPOPERATIONS TO BE CARRIED OUTTEST RESULTS
0PRELIMINARY CHECKSALL OKPROBLEMS ENCOUNTEREDACTION
Check the condition of the air intake circuit.Check condition of the air filter and ensure it is working properlyMove on to Step 1Air intake circuit faultyRenew the air intake circuit
Filter blockedReplace the filter element Op. 1048A14 AIR CLEANER FILTERING ELEMENT - REPLACE.
1CHECK USING DIAGNOSTIC EQUIPMENTALL OKPROBLEMS ENCOUNTEREDACTION
Connect the diagnostic equipment to the diagnostic socket.Check:
  • that there are no errors in the control unit;
  • parameter plausibility
Move on to Step 2Error detected in the control unitContinue following the instructions for the diagnostic equipment
Parameters not plausibleContinue following the instructions for the diagnostic equipment
No communication with the control unitRestore the connection between the engine management control unit and the diagnostic connector See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT
2FUEL FILTER CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check fuel filter operationMove on to Step 3Water, petrol, paraffin or dirt found to be presentClean the tank and pipes and replace the filter element Op. 1044B20 FUEL FILTER FILTERING ELEMENT - REPLACE
3INJECTOR CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check for diesel leaks from the injectors See Test 1060O DIESEL FUEL INJECTION SUPPLY TESTSMove on to Step 4One or more injectors found to be leakingChange the injectors Op. 1060F10 FUEL INJECTORS
4EGR VALVE CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check EGR valve operation following removalMove on to Step 5EGR valve blocked openReplace the EGR valve Op. 1080C10 E.G.R. VALVE - R + R
5VALVE CLEARANCE CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Check that the tappet clearance is correct Op. 1036H14 VALVE TAPPETS - CHECK CLEARANCEMove on to Step 6Valve clearance not correctAdjust the tappets Op. 1036H10 VALVE TAPPETS - CHECK AND ADJUST CLEARANCE
6CYLINDER COMPRESSION CHECKALL OKPROBLEMS ENCOUNTEREDACTION
Carry out the cylinder compression checkMove on to Step 8Cylinder compression insufficientMove on to Step 7
7CHECK ON CAUSE OF INSUFFICIENT COMPRESSIONALL OKPROBLEMS ENCOUNTEREDACTION
R/R head for valve leakage test. Op. 1016C10 SINGLE CYLINDER HEAD, REMOVED - OVERHAULCheck condition of cylinders/piston ringsMove on to Step 8Valve seal insufficientOverhaul the head Op. 1016E10 SINGLE CYLINDER HEAD, REMOVED - OVERHAUL
8CHECK ON CORRECT OPERATIONALL OKPROBLEMS ENCOUNTEREDACTION
Check that the fault is no longer presentEnd of diagnosisFault persists: control unit defectiveReplace the engine management control unit Op. 1060G80 DS ELECTRIC INJECTION CONTROL UNIT - R R