939005386 - D001 ENGINE NOT RUNNING SMOOTHLY / (HESISTANT)

There are momentary failures in the response to pressing the accelerator pedal. This condition may take place at any vehicle speed. This condition is usually more pronounced when setting off again after a stop and can also cause the engine to stall if it is serious enough.
Test results
0PRELIMINARY CHECKSAll OKProblems encounteredOperation
Before starting, check that the MIL warning light is on and that it goes off once the engine has been started. Also check that no accessories have been fitted in the after-marketMove on to Step 1The MIL warning lights does not come on when the key is insertedContinue as instructed in the    See table K100 MIL WARNING LIGHT NOT WORKING (REMAINS OFF BEFORE STARTING)
The MIL warning light remains on with the engine startedContinue as instructed in the    See table K101 MIL WARNING LIGHT STAYS ON (ENGINE STARTS)
There are accessories that have been fitted in the after-marketCheck that these accessories have been fitted correctly
1CONTROL UNIT ELECTRICAL CONNECTIONS CHECKAll OKProblems encounteredOperation
Check that the electrical connections for the engine management control unit are correct    See E5030 PETROL ENGINES ELECTRONIC MANAGEMENT In particular, check that:- the earth is correctly connected- the resistance between the control unit    See M010 ENGINE MANAGEMENT ECU and the battery negative    See A001 BATTERY is less than 0.5 OhmMove on to Step 2Connection to earth incorrectRestore the correct connections
Resistance to battery negative more than 0.5 OhmRestore the correct connections
2CONTROL UNIT FASTENING CHECKAll OKProblems encounteredOperation
Check that the control unit is correctly fastened in its housing    Op. 1056F82 CONTROL UNIT SINGLE OF INJECTION IGNITION SYSTEM R R Move on to Step 3Control unit fastening incorrectRenew the correct fastening for the control unit    Op. 1056F82 CONTROL UNIT SINGLE OF INJECTION IGNITION SYSTEM R R
3AIR INTAKE CIRCUIT CHECKAll OKProblems encounteredOperation
Check there are no faults in the air intake circuit.In particular, check:- that the air filter is not blocked or fitted incorrectly- that the air intake circuit does not have any irregular constrictions, leaks or is fitted incorrectlyMove on to Step 4Air filter blockedReplace the filter element    Op. 1048A14 AIR CLEANER FILTER ELEMENT - REPLACE.
Irregular componentReplace the faulty component    Op. 1048 ENGINE AIR SUPPLY CIRCUIT
Component incorrectly positionedRefit the component correctly    Op. 1048 ENGINE AIR SUPPLY CIRCUIT
4LAMBDA SENSOR CHECKAll OKProblems encounteredOperation
Check that the Lambda sensor upstream of the catalyzer is working properly, by carrying out the    See Test 1080BA UPSTREAM LAMBDA SENSOR OPERATION CHECKMove on to Step 5Faults presentThe operation to solve the problem is described in the actual test
5FLOW METER ERRORS CHECKAll OKProblems encounteredOperation
Connect the diagnostic equipment and check that error P0100 is not presentMove on to Step 6Error P0100 is presentContinue as described by the diagnostic equipment
6FUEL FEED CIRCUIT CHECKAll OKProblems encounteredOperation
Check there are no faults in the fuel supply circuit by performing the    See Test 1040OA FUEL SUPPLY CIRCUIT CHECKMove on to Step 7Faults presentThe operation to solve the problem is described in the actual test
7CHECK FOR THE PRESENCE OF IMPURITIES IN THE FUELAll OKProblems encounteredOperation
Check that there are no impurities such as water, alcohol or particles in suspension in the fuel by carrying out the test    See T FUEL QUALITY CHECKMove on to Step 8Faults presentThe operation to solve the problem is described in the actual test
8INJECTOR CHECKAll OKProblems encounteredOperation
Check that the injectors are not stuck shut or not perfectly closed by carrying out the    See Test 1056BA INJECTOR OPERATION CHECKMove on to Step 9Faults presentThe operation to solve the problem is described in the actual test
9IGNITION COIL CHECKAll OKProblems encounteredOperation
Check that the ignition coils are correctly fitted in their seats. Also check that they do not show signs of corrosion or dampness.Lastly, check that the ignition coils are working properly, by carrying out the    See Test 5510CC IGNITION COIL CHECKMove on to Step 10One of the coils is not fitted correctlyRefit the coil correctly    Op. 5510C14 IGNITION COIL/S - R.R.
One of the coils shows signs of corrosion/dampnessReplace the coil    Op. 5510C14 IGNITION COIL/S - R.R.
One of the coils is not working properlyThe operation to solve the problem is described in the actual test
10SPARK PLUGS CHECKAll OKProblems encounteredOperation
Remove the spark plugs    Op. 5510D10 SPARK PLUGS - R+Rand check that they are no signs of faults, following the instructions in the test    See T SPARK PLUG STATE CHECKMove on to Step 11Faults presentThe operation to solve the problem is described in the actual test
11RPM SENSOR CHECKAll OKProblems encounteredOperation
Check that the resistance value of the rpm sensor in all temperature ranges is between 700 and 1200 OhmMove on to Step 12Resistance values outside of the rangeChange the rpm sensor    Op. 5510C26 ENGINE RPM SENSOR - R+R
12PHASE TRANSFORMER ERRORS CHECKAll OKProblems encounteredOperation
Connect the diagnostic equipment and check that none of the following errors is present: P0011, P0014Move on to Step 13One or more of the errors indicated is presentContinue as described by the diagnostic equipment
13ALTERNATOR CHECKAll OKProblems encounteredOperation
Check that the alternator output voltage is between 9 and 16 VMove on to Step 14Output voltage below 9 VCheck that the alternator is working properly by carrying out the    See Test 5530AB Check alternator operation
Output voltage above 16 VReplace the pressure regulator    Op. 5530A24 ALTERNATOR VOLTAGE REGULATOR - R.R. WITH ALTERNATOR REMOVED
14CHECK ON CORRECT OPERATIONAll OKProblems encounteredOperation
Check the fault has disappearedEnd of diagnosisThe fault persistsContact the Technical Expert for further information on the problem