Four possibilities; Firstly it could be the EGR valve sticking.
Secondly, there are two fuel pumps on these systems - one under the bonnet, and one by the fuel tank. Either can give trouble, and assuming that the inline one you've renewed is under the bonnet, the tank one is a possibility. I would, though recommend taht you have this possibility tested for first by a garage with a fuel pressure testing rig as the pumps are around £200 each.
Thirdly - it could be the air mass meter playing up; they're about £150 from dealers , but can be found on ebay for around £80-£100ish. The normal symptom of a failed air mass meter is very flat performance - this develops into cutting out if left.
Finally, it could be that the Electronic control unit has flooded. This sits in a small compartment on the bulkhead nearside - which has a couple of drain holes underneath. These can get blocked, meaning the box fills up with rainwater, causing the ECU to be damaged. They do sometimes dry out satisfactorily if removed and left in a warm place for a weekend, but if not a new one is needed, and they, unfortunately, are about £800...
Peter Simpson (sold 50 Rover 75s on ebay!!), January 2008
