Affecting: Early Hdi Variants
Sadly another fairly predictable fault. Fuel lift pump failure on every Hdi version. If your Hdi has died on you, occasionally a hefty thump and a hearty expletive will get her going again temporarily. The bit to swear at is the fuel pump/sender unit located in the fuel tank (under the rear seats on most models). You may be able to 'limp' home albeit with little power. A replacement pump unit will usually bring performance and reliability back into the realm of normalcy.
Pumps in general www.eurocarcare.net/fuel-pump.html