Not starting Vivaro?

I have a Vauxhall Vivaro van on a 2003 plate with a 1.9 cc engine 5 speed gear box. All was working well until yesterday morning when it started ok first thing, but when I switched it off, it would not start again.

The engine turns over fine but it will not fire. I have had a mobile mechanic come out and have a look at it, and his diagnostics machine picked a fault that indicated low pressure fuel to engine.

I have done some reading up on this via the haynes manual, and it is a very complicated job to take out the high pressure fuel pump, and re-fit. I have also found out that a new pump may cost me up to £500, which I really can't afford right now.

My question to anyone is

If i bought a recon fuel pump and had it fitted, would it also have to be programmed into the ECU unit, which will cost more money!!

Can anyone help with any suggestions please?

Regards to all