I would check the fuel pump relay. I had the same problem. Fuel injector grounds are ran through the relay I believe. You should have 7 or 8 fault codes dealing with ground issues. Relay is under the dash.
My Bentley manual shows it being a type 409 from the earliest production in 1998. It has probably been replaced before.The old relay I have is stamped 167 from my '98. Looks like the numbers can vary. Picture on link shows 409.