312000555 - D002 ENGINE NOT RUNNING SMOOTHLY / (LOSING POWER)

Momentary lack of response when the accelerator pedal is pressed. Can happen at any speed. Usually it is more obvious when trying to get the vehicle to set off, for example after a stop.
Test results
0PRELIMINARY CHECKSAll OKProblems encounteredOperation

Check the following, in order:

  • no leaks in fuel circuit;
  • condition of the air intake circuit;
  • no obstructions in the catalytic converter;
  • no water or impurities in the fuel
Move on to Step 11. Fault in the air intake circuit2. Obstruction in the catalytic converter3. Water in the fuel4. Leaks in fuel circuit1. Renew the air intake circuit2. Replace the catalytic converter    Op. 1080B62 CATALYTIC CONVERTER - R + R 3. Remove water from the fuel4. Eliminate leaks.
1CHECK USING DIAGNOSTIC EQUIPMENTAll OKProblems encounteredOperation
Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket.

Check:

  • that there are no errors in the control unit;
  • parameter plausibility.
Move on to Step 21. Error detected in the control unit2. Parameters not plausible1. Continue following the instructions on the diagnostic equipment2. Continue following the instructions on the diagnostic equipment
2ACCELERATOR PEDAL CHECKAll OKProblems encounteredOperation
Using the Examiner, check that the signal reaches 100% when reading the parameters and goes to the end of travel positionMove on to Step 31. Accelerator pedal travel incorrect2. Accelerator pedal potentiometer defective1. Restore the accelerator pedal travel2. Replace the accelerator pedalOp. 1068A14
3CHECK THE OPERATION OF THE MOTORIZED THROTTLEAll OKProblems encounteredOperation
Check the condition of the motorized throttle actuator connectionCheck the condition of the wiringCheck that the motorized throttle is working properly, carrying out    See Test 1056BW THROTTLE BODY ACTUATOR OPERATION CHECKMove on to Step 41. Connection defective2. Wiring defective3. Motorized throttle defective1.Restore the correct connection.2.Restore the correct wiring.3.Replace the motorized throttleOp. 1056B14
4IGNITION SYSTEM CHECKAll OKProblems encounteredOperation

Inspect the spark plugs, checking:

  • for possible electrode wear;
  • carbon deposits;
  • for any damage to the spark plug insulator;
  • the correct distance between the electrodes
  • the correct AT signal, by carrying out the
    See Test 5510OA IGNITION COIL RESISTANCE CHECK, the    See Test 5510CI IGNITION COIL OPERATION CHECKand the    See Test 5510CE IGNITION CONTROL SIGNAL CHECK		Move on to Step 51. Spark plugs defective2. Coils defective1. Replace spark plugs    Op. 5510D10 SPARK PLUGS - R+R2. Replace coils    Op. 5510C14 IGNITION COIL/S - R.R.
5INJECTOR CHECKAll OKProblems encounteredOperation
Using the Examiner, check in active diagnosis that all the injectors are working properly. Identify any injector that may be mechanically stuck shut.Injector wiring check    See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT Check that the injector opening signal is correct by carrying out the    See Test 1056BA INJECTOR OPERATION CHECKMove on to Step 6Injector defectiveReplace the injector    Op. 1056B70 INJECTOR (ONE) - R + R WITH FUEL MANIFOLD PIPE REMOVED - INCLUDES SEAL REPLACEMNT
6ELECTRIC PUMP CHECKAll OKProblems encounteredOperation
Check that the electric pump is working properly by carrying out the    See Test 1040AB SUBMERGED FUEL PUMP CHECKCheck the correct earth connection    See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT Move on to Step 71. Connection to electric pump earth defective2. Electric pump defective1. Restore the correct earth connection.2. Replace the electric pump    Op. 1040A70 SUBMERGED PUMP ASSEMBLY COMPLETE WITH LEVEL GAUGE CONTROL - R + R
7CORRECT OPERATION CHECKAll OKProblems encounteredOperation
Check that the fault is no longer presentEnd of diagnosisThe fault persistsReplace the engine management control unit    Op. 1056B82 INJECTION/IGNITION SYSTEM E.C.U. (ONE) - R + R