The correct way to test is via fuel delivery rate and system pressure as follows.
Fuel Delivery Rate:
* Remove number 28 fuse.
* Make up wire that has a switch in it.
* Connect one end of the wire to the contact at the fuse box where you removed the fuse.
* Connect the other end to the battery +12v terminal (don't switch on yet)
* Remove the fuel delivery pipe and put it into a measuring jug. Pipe No.2 in the diagram.
* Attach a voltmeter across the terminals of the battery.
* Turn on the switch in the lead to run the pump. Run it for 15 seconds and remember the voltage reading whilst its running.
* Compare the amount of fuel delivered with this diagram. It's a graph of minimum delivery Vs voltage. Voltage can be a couple of volts lower than when the car is running. This is okay.
System Pressure and holding test:
* Connect a pressure gauge with cut off valve inline within the fuel delivery pipe
* Run the engine. Pressure gauge should read 2.5bar
* Disconnet the vacuum pipe from the fuel pressure regulator. The pressure should rise to 3bar.
* Turn engine off and watch the gauge. After 10 minutes the gauge should still read a mimimum of 1.5bar.
To locate the injector rail. Remove the main engine cover. Look at the inlet manifold. On top of the runners you'll see the injectors. The metal pipe connecting them is the rail. On the right hand side at the end of it is the fuel pressure regulator.