Patent ID: 7835852

Claim:
A detector for detecting the operational status of one or more of a plurality of fuel pumps in a fuel system of a vehicle, the system comprising an accumulator volume for storing high pressure fuel, one or more injectors arranged in fluid communication with the accumulator volume and a plurality of high pressure fuel pumps arranged in fluid communication with the accumulator volume so as to supply high pressure fuel thereto, the operation of the fuel pumps being controlled by a filling pulse signal from a control means, the detector comprising inputs for receiving data representing at least one current system parameter processing means arranged to compare the at least one current system parameter against one or more predetermined system parameters in order to identify the operational status of the fuel pumps wherein each fuel pump comprises a pumping chamber within which fuel is pressurised by an associated pumping plunger, the pumping plunger being driven by a cam drive arrangement and the drive motion imparted to the pumping plunger by the cam drive arrangement being a characteristic of the system wherein the processing means compares the at least one current system parameter with the drive motion of the cam drive arrangement, the presence of the drive motion superposed onto the current system parameter indicating a reduction in the operational status of one or more of the fuel pumps, and; wherein the drive motion applied to a first fuel pump is phased in relation to the drive motion being applied to neighbouring fuel pumps wherein the processing means compares the current system parameter with the drive motion as applied to the plurality of fuel pumps in order to determine the operational status of each fuel pump.