DT466E / Code 333

Hi,
I'm in deep!!! I'm working on a 2000 Int./4700 w/a DT466E. I keep getting a code 333(injection pres. above/below desired spec). I did some volt & ohms
tests on the IPR & ICP sensor,they seem to be OK.The truck already has a
new high pres. oil pump & regulator in it already. I replaced the injector seals because I thought a couple of them were leaking. Sometimes the code will
set right after startup,other times it won't set until you drive it (less than a
1/4 mi).If I hook up the Pro-Link scanner & monitor the pres. when it's cold,
it's around 1200-1300 PSI. As soon as the code sets it drops to 750(Limp Mode). The code will also set if I run the Standard Running Test.

Fault Description:
333-(1) If set during normal engine operation indicates engine is operating in open loop control & ICP pressure is above or below desired pressure.

(2) If set during engine running test, indicates ICP system failed step test & could not maintain commanded pressure.

Possible new pump is bad?

:bang