Not to dispute anything Marshall has said, but I did replace the seals & o-rings on the albatross's pump when a couple of them started leaking after it'd been sitting idle for 6-8 weeks. Replacement did cure that problem. Per Marshall's suggestion, I would rule out everything else first, but if you do decide to do this, you'll want to torque the fittings using the specs in the TDM rather than the fsm; just ask for this if you decide to go ahead. Have you tried cracking the injection lines one by one with the engine idling in an attempt to isolate the problem to one or more cylinders? Don't remember if you've definitively ruled out a balky injector.
joe
