Well, if you are sure of the ICP pressure value, then it is either a standpipe leak, an injector leak, or an oil rail leak.

Leak testing at each rail (or through the IPR port) is recommended. Do so with the valve cover off and listen real well at each injector.

 

can I use the ICP port? I don't have the fitting for the IPR

 

Yes you can. It is slightly less reliable because an IPR issue can cause you to fail the testing. On the later year models it isn't as effective because the ICP is on the passenger oil rail and the air has to flow in reverse direction past the passenger standpipe.

Since you are sure of the IPR valve, then it is no issue.

 

i think I could air charge the oil rails directly. If I use the ICP port do I need tp power the IPR to open it?

 

The IPR is a "bleed-off" valve. The only flow past it (or through it) is the oil bleed flow to the crankcase. You must close the IPR valve to do the air test. Even if you pressurize the individual oil rail through a rail plug, the IPR needs to be commanded closed.

 

So I finally did the air test on the individual oil rails. Got some serious gurgling. Used my stethoscope and found the gurgling to be strongest at the top of the stand pipes. about equal on both sides even when air to only one side. it was pretty loud. could this be the drain off on the pump? I will remove the stand pipes and re O ring. Then re-air test. any thoughts?