This could be related to anything from your CPS to high pressure oil pump to the ICP to fuel/fuel pump (a likely culprit).
Start at the fuel filter (located pretty much top dead center of the engine) as it may be clogged. From there, take a look at the fuel pump (common problem) which is on the frame under the drivers side. Take notice if it is making any unusual noise (ie loud whine or buzzing).
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Maybe somebody else will offer up more immediate advice but in the mean time, give that a shot and see what happens