Right, but how do you know it's doing that with the filter on? What filter are you using? If it's an OEM (motorcraft or International) you should be fine, but with the aftermarket filters that use their own cap, sometimes they don't hold that button down right. When's the last time the filter was changed?


BTW, I'm just going to reply in this thread now instead of both of them haha.

 

Ford did the oil change so I a sure it a dealer part

 

Ok that's good to know. I know it seems silly, but have you checked the oil level too? Does the o-ring on the oil filter cap look good?

Here's a good read on the oil filter differences just for fun, page 3 is the one you want to pay attention to: https://www.dieselbombers.com/ford-p...ke-switch.html

With that said, if the gauge on the dash is dropping that means your oil pressure is falling REALLY low, I think the dash gauge only needs something like 5psi to even register, so if it's falling below that, then there's some serious issues. I would almost want to put a stand alone mechanical gauge on it just to verify that.

 

Right but when it does start every once in a while the oil pressure is good except for at idle but I have only go it started three times in a week almost every one I have talked to say hoop cause that but

 

Well if you want you can verify the HPOP is working with a scanner. Monitor ICP actual and ICP desired. But if the low pressure oil is falling off, obviously the high pressure readings are going to be wrong too... if the low pressure pump can't supply oil to the high pressure pump, you'll have low high pressure readings, but not because of the high pressure pump itself. See what I'm getting at? It's apparent there's an issue with the low pressure oil coming in if the gauge on the dash is falling off.

Again, you've checked the oil level right? I don't think you ever verified it. How long has it been since the oil was changed on it?

 

I had this problem and it was the O rings on my left Bank. I pulled the valve covers , removed the the thickem . I had my friend who is a diesel tech at Ford crank it and watched to see which injector was leaking at the top by the fuel rail. I found two that were leaking. I replaced all the 0 Rings on that side. Torqued everything back to spec. High pressure oil leaks suck. Not sure that this is your problem but sure sounds like it may be. Very important to replace all the O rings on each injector on the whole bank of the motor. I did all 4 injectors , not to bad.