D02 ENGINE NOT RUNNING SMOOTHLY / (LOSING POWER) - Alfa - 147 - eLearn

3022580 - D02 ENGINE NOT RUNNING SMOOTHLY / (LOSING POWER)

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

Results of the tests

PRELIMINARY CHECKS

All OK

Problems met

Operation

Check, in order:

that there are no leaks from the fuel system
the condition of the air intake circuit
that there are no obstructions in the catalyzer
that there is no water in the diesel filter

Continue to Step 1

Fuel leaks

Eliminate the water from the diesel

Fault in air intake circuit

Repair the air intake circuit

Obstruction in the catalyzer

Replace the catalyzer

Water in diesel filter

Clean the tank and replace the filter

CHECKING WITH DIAGNOSTIC EQUIPMENT

All OK

Problems met

Operation

Connect the diagnostic equipment (Examiner or other instruments) 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

An error is detected in the control unit

Continue following the instructions for the diagnostic equipment

Unreliable parameters

Continue following the instructions for the diagnostic equipment

ROAD TEST WITH DIAGNOSTIC EQUIPMENT

All OK

Problems met

Operation

Road test the vehicle keeping the diagnostic instrument connected.

Make sure that the conditions in which the problem occurs are reproduced

check

for errors in the control unit
plausibility of all the parameters

Continue to Step 3

Errors suddenly occur in the control unit

Continue following the instructions for the diagnostic equipment

Parameters off scale

Continue following the instructions for the diagnostic equipment

CHECK ON BRAKE PEDAL SWITCH

All OK

Problems met

Operation

Check that the pedal switch is working properly See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT

Continue to Step 4

Brake pedal does not return

Eliminate the cause of the sticking

Switch faulty

Replace the switch

Wiring short-circuit (intermittent)

Restore connection See E5030 PETROL ENGINE ELECTRONIC MANAGEMENT

CHECK ON CORRECT OPERATION

All OK

Problems met

Operation

Check that the fault is no longer present

Fault persists: control unit defective

Search for the fault starting from another symptom'