312002005 - S003 ENGINE KNOCKING

The customer complains that: Irregular combustion noise, engine cylinder head knock
Test results
0PRELIMINARY CHECKSAll OKProblems encounteredOperation
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.Check the condition of the fuel supply circuit and make sure that it is working properly.Check the operation of the low pressure supply circuit by carrying out the.    See Test 1060OB LOW FUEL DELIVERY PRESSURE CIRCUIT CHECKMove on to Step 1Oil level incorrect.Restore the correct engine oil level    Op. 0010T11 ENGINE OIL - CHECK LEVEL AND TOP UP, IF NECESSARY
1MODE PARAMETERS CHECKAll OKProblems encounteredOperation
Select the following control unit at the diagnostic equipment: Marelli 6F3 electronic injection control unit.

Check the value of the following parameters:

  • Battery voltage
  • Atmospheric pressure
  • Air temperature in the intake manifold
  • Supercharging pressure Objective
  • Supercharging pressure Measured
  • Measured air mass
  • Engine coolant temperature
  • Diesel temperature
  • Target diesel pressure
  • Measured diesel pressure
  • Engine rpm
Move on to Step 2
2PREHEATING RELAY ACTIVE DIAGNOSISAll OKProblems encounteredOperation
Carry out the active diagnosis for the preheating relay, checking that the result is positive.
The check on the following system is only necessary if the outside temperature is below 0 °C.
End of diagnosisThe result of the active diagnosis is negative.Move on to Step 3
3GLOW HEATER PLUGS CHECKAll OKProblems encounteredOperation
Check that the glow heater plugs are working properly, by carrying out the    See Test 5520CA GLOW HEATER PLUGS OPERATION CHECK