3233005 - B12 ENGINE STARTS WITH DIFFICULTY' / WHEN COLD

When the outside temperature is low, the engine does not start when cold, or it starts with difficulty and only after repeated attempts. When the key is turned the instruments light up normally, the starter motor turns, but the engine does not start
Results of the tests
0PRELIMINARY CHECKSAll OKProblems metOperation
Preliminarily check that the voltage is correct and that the battery is working properly

Then, check:

  • state of the spark plugs and leads
  • condition of the air intake circuit
Continue to Step 1 Battery run downRecharge or replace the battery
Spark plugs dirty or damaged Clean or replace the spark plugs Op.   5510D10 
Spark plug leads damaged Replace the spark plug leads Op.   5510D14 
Air intake circuit component damagedReplace component (see Assembly 1048A)
1CHECK USING DIAGNOSTIC EQUIPMENTAll OKProblems metOperation
Connect the diagnostic equipment (Examiner or other instruments) to the diagnostic socket

Check:

  • that there are no faults in the engine management control unit
  • the plausibility of all the parameters
Continue to Step 2 Error detected in the control unitProceed according to the instructions for the diagnostic equipment
Failed dialogue with the control unit Restore the connection between the engine management control unit and the diagnostic connector ( See   E5030  PETROL ENGINE ELECTRONIC MANAGEMENT )
2CYLINDER COMPRESSION CHECKAll OKProblems metOperation
Carry out the cylinder compression test Op.   0510A10  . Continue to Step 3 Compression values not correct Restore the correct cylinder compression, for example, checking the seal of the injectors Op.   1056B70  and the cylinders (see ENGINE OVERHAUL, Subassembly 1004)
3FUEL PRESSURE CHECKAll OKProblems metOperation
Check the fuel supply pressure Op.   0510C10  , Continue to Step 4 Pressure not correct Replace the fuel pump assembly Op.   1040A70 
4INJECTORS CHECKAll OKProblems metOperation
Using the diagnostic equipment (Examiner or other instruments) carry out an active diagnosis for the injectors Continue to Step 5 Injectors connectino faulty Restore the injectors connection with the control unit,( See   E5030  PETROL ENGINE ELECTRONIC MANAGEMENT )
Injectors faulty Replace injectors Op.   1056B70 
5CORRECT OPERATION CHECKAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persistsSearch for the fault starting from another symptom'