Question to all JTD 1.9 8V (Multijet with EDC16) drivers and mechanics: What exactly is the most common cause of error code P0503? I take that it is not the tach generator as per the generic OBD list, as everything related to it is working fine (speedo, esp, anti-lock, 4wd).
Some other list on the net indicates that FIAT repurposed that code as an early warning for HP fuel system problems ("OBD/2 P0503 error code:
Fuel Rail Pressure Sensor in Range But Low")
Indeed I get the impression that the engine can be reluctant to start, especially after it has been sitting for a few days in the cold. So where would you start looking? Leak back test on injectors shows no irregularities, neither do the correction factors. No easily visible fuel leaks either...
Some other list on the net indicates that FIAT repurposed that code as an early warning for HP fuel system problems ("OBD/2 P0503 error code:
Fuel Rail Pressure Sensor in Range But Low")
Indeed I get the impression that the engine can be reluctant to start, especially after it has been sitting for a few days in the cold. So where would you start looking? Leak back test on injectors shows no irregularities, neither do the correction factors. No easily visible fuel leaks either...
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