312000561 - D012 ENGINE IDLING TOO LOW

The customer complains that: Engine idle speed is too low
Test results
1MODE PARAMETERS CHECKAll OKProblems encounteredOperation
Connect using the Examiner in the engine control unit and

Check the value of the following parameters:

  • Battery voltage
  • Accelerator pedal
  • Accelerator position 1 AD/C
  • Accelerator position 2 AD/C
Move on to Step 21. Battery voltage low2. Accelerator pedal potentiometers defective1. Recharge/replace battery2. Replace the accelerator pedalOp. 1068A14
2MOTORIZED THROTTLE CHECKAll OKProblems encounteredOperation
Check that the motorized throttle is working properly, carrying out    See Test 1056BW THROTTLE BODY ACTUATOR OPERATION CHECKCheck the continuity of the wiring between the engine control unit and the motorized throttle    See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT Move on to Step 31. Motorized throttle defective2. Wiring defective1. Replace the motorized throttleOp. 1056B14 2. Restore correct wiring.
3CYLINDER COMPRESSION CHECKAll OKProblems encounteredOperation
Carry out the cylinder compression checkOp. 0520G15 Move on to Step 4Cylinder compression insufficientMove on to Step 5
4CHECK THE CAUSE OF THE INSUFFICIENT COMPRESSIONAll OKProblems encounteredOperation
Carry outOp. 1016C10 to check the valve seal and the condition of the cylinders/piston ringsMove on to Step 5Valve seal insufficientOverhaul the cylinder head    Op. 1016E10 SINGLE CYLINDER HEAD, REMOVED - OVERHAUL
5CORRECT 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