With the engine warm and idling, with all electrical users off and the accelerator pedal not operated, the air temperature in the intake manifold must be in a range between 10 and 120 °C.

The test can be considered over

Turn the ignition key OFF.

Disconnect the cable loom connector from the fuel pressure regulator on the rail.

See N077 FUEL PRESSURE REGULATOR

Turn the ignition key ON.

Measure the voltage between Pins 2 and 1 of the regulator to ensure they are not in the range between 4.8 and 5.2 V

See N077 FUEL PRESSURE REGULATOR

If faults are present, repair or if necessary replace the electrical wiring between the engine control unit and the tubocharging sensor.

See E5050 DIESEL ENGINES ELECTRONIC MANAGEMENT

The test can be considered over

Replace the engine management control unit

Op. 1060G80 DIESEL ELECTRONIC INJECTION CONTROL UNIT - R.R

Measure the voltage between Pin 2 of the regulator and Earth to ensure it is in the range between 4.8 and 5.2 V

See N077 FUEL PRESSURE REGULATOR

Replace the engine management control unit

Op. 1060G80 DIESEL ELECTRONIC INJECTION CONTROL UNIT - R.R

Connect an upstream connection lead with a fuse between Pin 2 of the regulator and Earth. Check that the air temperature in the AD/C intake manifold is now less than 0.3 V

See N077 FUEL PRESSURE REGULATOR

Replace the engine management control unit

Op. 1060G80 DIESEL ELECTRONIC INJECTION CONTROL UNIT - R.R

Replace the turbo sensor

Op. 1060G16 EXCESS PRESSURE SENSOR - R.R.