Fuel Starvation/ fail to start

So, just a quick story of my last few days. Go to van, not run it for a week or so, turn key, heater light goes out, start van. Runs a few seconds and cuts out. Try again, the same happens. Next time rev it a few seconds then it cuts out. Next start is a higher speed whining turn over and nothing. A bit worrying on the face of it, timing gear failure? Fuel pump failure? It did seem like fuel starvation. 

So recovered to dealer via a friend's slide deck truck. FOC fortunately, as it's over a year old now and no free recovery. 

Problem, the van on turning over was only putting out 8 Volts. The BCM turned of the electric fuel pump. No warnings or fault codes. Van was on an incline and had drained out the mechanical fuel pump. The short time I ran it dry so with no resistance of fluid pressure the turn over was smooth and fast. Doh. 

New battery fitted under warranty and started up first time perfectly. 

You'd think the fact I have to keep charging it to stop the Ford App messages as it's not used much might have been a hint!

Lesson:

Never forget the basics.