Possibly your hpop. When your oil is cold it allows pressure to build , not so much when oil is hot.

 

So the Hpop is new has only a few hundred hours on it. Could it be the pump or possibly just an o ring or seal somewhere on it?

 

Start with the air test -- thru the IPR port works best -- the fittings are pretty cheap and an air tester can be made up easily, use a short hose (air tool whip hose works well) with a ball valve at the airhose fitting end -- turn the air on for at least 10 minutes to blow out any oil thru the leak -- 150 psi is recommended, but use whatever you have

When you pull the IPR to do the air test, pay attention to the screen on the tip of the valve -- if there is a hole in it, that means junk has been forced into the valve -- there is a cleaning procedure, but for most people just replace the valve

A "tight" system will have no air leaks at 150 psi -- if you tee a gauge into your tester, it will hold pressure for quite a while

 

Why do so many people want to replace the 05 and up HPOP??

 

Well, Parts changing it a form of troubleshooting, right?

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If the system is leak free when testing through the IPR port, AND it still only gets to 330 psi or so, my bet would be on the IPR valve.

 

There's always the "it's new so it must be good" theory too. This comes with the "I replaced that, so I'll replace something else" theory.

If it starts when cold, but not once warmed up, you have a leak in the high pressure system. Probably a stand pipe seal, but the ipr seals (and junk in the ipr) can cause this to.

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Don't forget about the wreched STC fitting. I'm not sure if that will come up on an air test though.

 

I don't know, never tested mine with the oem fitting. I'd ASSume the stc fitting was addressed when the new pump went in.

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Were OEM standpipes and dummy plugs used?

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I used oem "upgrades" and that center O-Ring where they connect together still blew. It happens, that's why you trouble shoot before buying parts.

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Prolly scared him off

 

What Hydro said...

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Check with a pressure test gauge at the oil pressure switch, after warn up 12 to 30 is OK accelerate might be 70 is ok.the ICP must be more than 485 & mine was 575 after warn up when accelerate reach 1500 shut the engine after 1hour1/2 cranking again and engine start. Problem was g9t won't start. Ca7se the oil pressure switch was bend and the instrument cluster don't read the one that tell computer. but thank you! Jesus problem solved.

 

The most important is the reading ....