Fuel Inj Startup Fault

[jevansio]

Hi guys, I realise there are a few topics on this issue but would appreciate some advice on mine.

At startup I sometimes got this fault, whenever it came up it wouldnt start and would be accompained with the lack of fuel pump noise.  A quick turn off and on and the pump would whir and it would start.

I assumed it was the relay, and for $18 thought it safer to replace as a maintenance measure.  It seemed to help, but last few days the car would do the same thing (only ever after standing over night tho).  I have also just fitted a new heavy duty battery.

I'm obviously aware that the pre-supply pump could be the problem.  But why does a quick turn off & on cause it to start pumping 2nd time.  Also if i read the error codes will the problem code indicate the pump itself or will I have to assume its the pump dependig on what code values come out?

PS just pulled off codes, got 4b90 rail pressure at engine start, but I'm assuming this is "due" to the pump not firing rather than being the cause of it?

ta

Jay