I had a breakdown not long ago, caused by the fuel pump not running. I tracked it down to the fuel pump relay, which is located near the OVP, under the hood, at the back, near to the ECU & ABS ECU. It's black, somewhere between a matchbox and cigarette packet in size, and has 'Kickdown' written on (poss. older versions only). It has around 7 pins down one side, 3 on the other if you pull it out.
Listen to this - it should 'tick' audibly when you switch the ignition on.. and again 1 second later. If it doesn't, it may be your problem.
Mine *was* ticking.. but wasn't actually engaging the power fully. I would've replaced it but traced the problem to a damaged solder-join. Problem solved!
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black