Workshop Manuals Factory service & repair Fiat
01 General information02 Specifications03 Manufacturing data and tolerances04 Tightening torques05 Fluids and lubricants06 Maintenance07 Diagnostic checks08 Engine09 Clutch10 Gearbox and differential11 Axles and driveshafts12 Brakes13 Steering14 Suspension and wheels15 Heating, air conditioning and auxiliary units16 Electrical equipment17 Body fittings18 Body panels and frame19 Wiring diagrams and electrical functions20 Wiring harnesses21 Connectors and pin-outs22 Fault diagnosis23 Special tools
Fiat Idea Factory Service Manual (2003-2012)22 · Fault diagnosis
22 · Diagnostics

Engine not running smoothly / (losing power)

Make
Fiat
Model
Idea Factory Service Manual
Year
2003–2012
Section
Engine › Engine not running smoothly / (losing power)
Fault diagnosisEngine not running smoothly / (losing power)

ENGINE NOT RUNNING SMOOTHLY / (LOSING POWER)

1.4 16v

Under conditions of constant load and speed, there are intermittent decreases in performance, even prolonged

Results of the tests
0PRELIMINARY CHECKSAll OKProblems metOperation

Preliminarily check:

  • the state of the spark plugs and leads;
  • the condition of air filter
  • the condition of the air intake circuit;
  • absence of obstructions in the catalytic converter
Continue to Step 1Spark plugs dirty or damagedReplace the spark plugs Op. 5510D10
Cables damagedReplace spark plug leads Op. 5510D14
Air intake circuit faultEliminate the problem
Catalyzer obstructedReplace the catalyzer Op. 1080B62
1CHECK WITH DIAGNOSTIC EQUIPMENTAll OKProblems metOperation

Connect the Examiner diagnostic equipment to the diagnostic socket.

Check:

  • that there are no faults in the engine management control unit;
  • plausibility of all the parameters
Continue to Step 2'Supply system' error detectedContinue according to the instructions for the See table Z50 MIXTURE STRENGTH ERROR
'Misfire' error detectedContinue according to the instructions for the See table Z53 MISFIRE ERROR
Another error dectected in the control unitContinue following the instructions for the diagnostic equipment
Inconsistent parameterContinue following the instructions for the diagnostic equipment
2ROAD TEST WITH DIAGNOSTIC EQUIPMENTAll OKProblems metOperation

Road test the vehicle, reproducing the conditions in which the fault arises, keeping the diagnostic equipment connected.

Check:

  • that there are no faults in the engine management control unit;
  • plausibility of all the parameters
Continue to Step 3'Supply system' error detectedContinue according to the instructions for the See table Z50 MIXTURE STRENGTH ERROR
'Misfire' error detectedContinue according to the instructions for the See table Z53 MISFIRE ERROR
Sudden occurrence of another error detectedContinue following the instructions for the diagnostic equipment
Parameters inconsistentContinue following the instructions for the diagnostic equipment
3FUEL PRESSURE ROAD TESTAll OKProblems metOperation
Road test the vehicle and check the fuel supply pressure Op. 0510C10in the conditions that lead to the anomalyContinue to Step 4Insufficient fuel pressure: pipes obstructedRemove restrictions
Insufficient fuel pressure: valve obstructedReplace the tank cap Op. 1040A40
Insufficient fuel pressure: regulator out of calibrationReplace the pump assembly Op. 1040A70
Low fuel pressure: defective pumpReplace the pump assembly Op. 1040A70
Low fuel pressure: clogged filterReplace the pump assembly Op. 1040A70
4CHECK ON CORRECT OPERATIONAll OKProblems metOperation
Check that the fault is no longer presentEnd of diagnosisFault persists: control unit faultyReplace control unit Op. 1056B82

Parts & tools for this job For 2003 Fiat Idea

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