car wont start,
only have 4volts on supply side when ignition fired.
supplied separate 12 v to pump which primed and then it will start
leave for an hour pressure drops and wont start
does any one think, like me, this is a relay issue
or do you have any other ides.

 

ok all sorted:

changed fuel pump relay - still the same.
Turns out it was the crankcase position sensor - (very fiddley to change) but once changed all sorted

so the process was check fuel pump works with separate feed - yes - just lift base of rear seat and remove cover - 3 screws

replaced relay only cost a few quid so you know it is ok - yes - have to lower the dash lower drivers side to get to it

then go for the crankcase position sensor. got at from above but you have to remove quite a few bits and pieces to get to it.

bit long winded but at least gives a pattern of working and in order of difficulty to change/check