Technical Bulletin (Fuel Rail/System Pressure issues):
When diagnosing the condition above on a common rail diesel vehicle, if no root cause is found after checking all other components and all GFF diagnostic procedures have been performed, it may be necessary to check for metallic particles in the High Pressure Fuel Pump using the service section of this bulletin.
If such an inspection is necessary, the following guidelines in this document must be observed when removing the N290 Fuel Metering Valve. This document discusses the "Fault Codes" necessary to diagnosis, and potential remedy of issue. The fault codes for checking warranty coverage for servicing the vehicle are also available.