Engine would not run without oilpressure. Have you tested the oil pressure switch?

 

Not infamous and you are looking at the wrong oil system from what I can decipher form your post. I have replaced my share of oil pressure switches for either failing to close and indicate pressure or more commonly leaking oil. If you want to check oil pressure before spinning in a new sensor the minimum oil pressure specification is no less than 12 psi at 700 rpm at full operating temperature.

 

Replaced sending unit/swith three times. Along with pigtail. Replaced hpop and 3 times IPR with pigtail. Correct vehicle will not run without base oil pressure just to fire injectors. Air tested through IPR port and no leaks heard or detected with leakdown according to gauge on tester. Dead silent building with no radio and 4 sets of ears. Only at operating temp at red light in drive. Base idle set at 675 through sctx4

 

Replaced sending unit/swith three times.

I think someone famous (can't remember who right) now said: "The definition of insanity is doing the same thing multiple times and expecting different results."
I'm not trying to be disrespectful, but you need to do troubleshooting in a logical manner.
As Ford_Doctor said, you're looking at the wrong system. The dash gauge being inoperative has nothing to do with the HP oil system. If you've changed the sending unit and pigtail three times, you need to look downstream of there, towards the wiring to the instrument cluster and the instrument cluster itself. In order to work, the gauge needs continuity in the wire between the switch and the gauge. You should check that. A ground path is also needed for a complete circuit as well.

 

Maybe the dash gauge in the cluster is bad, or possibly a short in the wiring harness. You really should do a mechanical pressure test before spending any more money.

 

And I respect yalls points. I agree 100 percent. If this damn thing didnt have only 34k on it, Id be right with ya. This just started. And I am going to get a mechanical reading on base oil pressure, lpop if you will. Its only after I jump off the I-10, I really am leaning to a problem with bulletproof cooler/hose. I stronly believe its a problem with the hose from cooler to top of motor. Why? We kinked it once really bad pulling cab off.

 

Why would a hose cause no-pressure when hot?

 

I dont see this as electrical in any way. Yes heat makes resistance, knowledge taken, but its only when hot. Thats an oil/flow issue

 

Another new IPR and now ford seems to have just the screen without the triangle or thee plastic braces covering the screen. Its a brass screen now whereas the other ones were stainless I believe. Once it stops raining Ill go blast this damn thing to see the disappointment. Changed it due to no movement dtected or seen in plunger with snap on scanner moving full duty cycle. Hooked air to it and had leaks at all holes even with 12v hooked. New one from ford did the same thing but once it was pulled we said f it and put new one in anyway. Truck runs its butt off and Im rolling coal. All pids look great. This dang gause pees me off on the dash.
.

 

I think its restricting flow all the time. Just a hunch. Sorta like when a brake hose to a caliper is coming apart internally. You have pedal when applying but rubber/blockage wont let caliper compress. Its mandatory in my shop that every time we change a caliper a new hose goes on. I fought a caliper decades ago from this very issue. Since then we change hoses. Ahain, just a hunch. Fuel injector o-rings I havent totally ruled out. The top ring at spool

 

I would think that an oil hose that has flow and pressure at all times would not act like a brake hose.

 

Me too. Its not that easy lol

 

If you have all the power you expect and it runs great, I don't see how it can be in the high pressure oil system - anywhere.

A healthy high pressure oil system CAN pull down the pressure in the low pressure system if it isn't providing enough flow.

Are you sure that the oil filter drain valve isn't allowing oil in the filter housing to drain back to the oil pan? It can happen w/ a tall oil filter cap and an OEM filter, or if the drain valve is broken.

maybe the low pressure oil pressure regulator is sticking?

Without data it is all guess work.

 

If you have all the power you expect and it runs great, I don't see how it can be in the high pressure oil system - anywhere.

A healthy high pressure oil system CAN pull down the pressure in the low pressure system if it isn't providing enough flow.

Are you sure that the oil filter drain valve isn't allowing oil in the filter housing to drain back to the oil pan? It can happen w/ a tall oil filter cap and an OEM filter, or if the drain valve is broken.

maybe the low pressure oil pressure regulator is sticking?

Without data it is all guess work.

Bullet proof oil cooler. I do not have the oil filter up top anymore.

 

What exactly is your issue? Is it just that the oil pressure gauge doesn't work at all?

Your posts are all over the place and I for one have trouble following what the actual issue is. If it's just that the gauge doesn't work, but everything else is works OK (which you've indicated it does - as far as I can tell), then you have to look at the gauge and it's supporting wiring.

 

What exactly is your issue? Is it just that the oil pressure gauge doesn't work at all?

Your posts are all over the place and I for one have trouble following what the actual issue is. If it's just that the gauge doesn't work, but everything else is works OK (which you've indicated it does - as far as I can tell), then you have to look at the gauge and it's supporting wiring.

I was thinking the same thing.

 

Sorry, been out a bit and fighting the flu.

If I go on the interstate and get oil hot like anything above 210 then when I imediatly get off the interstate and hit a red light the oil pressure (gauge- low oil side) will drop to zero. Changed hpop, icp with pigtail, IPR a few times. All power is there. I have still yet to do a mechanical low pressure oil reading. It hasnt done it since last IPR from Ford but I also havent driven it to get oil temp up there yet.


Also yanked regulator in lower pressure pump again for a look see and its clean as a whistle.


Thanks

 

Edit - nm. I saw where you checked the regulator.

Now all that is missing is a mechanical pressure reading.

 

Look behind oil filter housing to the left. Find the one wire oil pressure switch. Cuss a lot as you find the release tab oriented in the spot making it hardest to depress to unplug wire. Unplug the wire connector and see if oil is in the connector. Replace the switch and see if problem is gone. The oil pressure switch is removed to check oil pressure and the fitting needed is a metric thread most oil pressure gauges you'll find won't have in the kit. The switch is $20 on amazon for Motorcraft SW5267. That is half the price of the auto stores for their off brand and you don't have to leave your house to get it next day if you have Prime.
As has already been said, the oil pressure switches fail on these engines and many other Ford models using that same switch. It can do it anywhere from 16 miles to 336000 miles and in one week or 14 years.
The oil pressure gauge is not a gauge on your truck. It goes to a fixed point when the oil pressure switch gets at least 8 psi (yes Ford lied to millions of customers for a couple of decades with this fixed point "gauge" system that is nothing more capable than an oil pressure warning light).

 

He stated that he replaced that switch THREE TIMES.

And STILL has yet to perform an oil pressure test with a mechanical gauge to see if this is an actual low oil pressure concern or not.

 

Correct, oil pressure (6-8 psi) switch has been replaced. I have to dedicate the time to install mechanical gauge to route in truck as a hand held deal and get her hot on the interstate then jump off and see what is actually occuring. I will post when done. I may just have fixed it with new IPR but have yet to find out. Ill post my results

 

Ok, ran it this am bringing son to school. Oil temp has to be at 220 or higher for this to happen. Only happens then and at red light in gear or in park. Idle must be 750 for light to go out and gauge to pop on. No mechanical pressure reading yet but I have to change the water pump (got BPD unit coming). I think Im going to change the lpop while there. Also going hydraulic fan clutch and yanking stator for trash can.
ICP: 782, ICP V: .9, IPR: 24%, EOT: 222, FICM: 48.5, Fuel PR: 59.2, EGT: 396 all at 650 idle with OP gauge zero.



Figure when water pump is off it is too easy not to yank the balancer and at least look at the gears. But I firmly believe thats where my issue lies. Air test through IPR hole reveals NO hp leaks.

 

Despite the advice, you are going to replace parts (the LPOP) BEFORE checking the pressure?? I truly don't understand why you have posted this thread if you don't respect the advice. You certainly may find an issue w/ the LPOP, but it really is a poor method of troubleshooting. You have spent a LOT of money already just guessing.

One thing I learned a long time ago is that the (very) knowledgeable Techs on these forums will go to great lengths to help you, but only if you listen to and heed the troubleshooting advice.

 

I agree with Bismic. The LPOP is NOT going to be your problem. That's going to be dumping money down the drain. It's about the last thing that would cause oil pressure to immediately drop, in any situation. LP oil pressure may degrade over time, but definitely won't heal itself when things cool down.
As has been advised, get a mechanical gauge on it to see what's really happening. With the oil pressure gauge being a pseudo-gauge that just responds to a switch, I would suspect a wire that's opening intermittently when the engine gets hot.

 

Point is well taken. If it were electrical and something is opening hot, then why if skinny pedal brings rpm up to 750 rpm does the problem go away?

 

Can't say about that, but I do know that intermittent electrical issues are a PITA to diagnose. Checking continuity while wiggling wire harnesses is essential, but sometimes even that won't work.

Good luck.

 

I don't know if 220 degree oil temp is normal for a BulletProof Diesel oil cooler or not, but if it were normal, I would be very unhappy with it. I have never seen over 210. Granted I only tow around 5000 lbs when I tow, but I see a LOT of hot days in the summer.

What has prevented you from getting a mechanical pressure reading? It should be simple, cheap, and take very little time at all.

 

Nothing really. What should my reading be cold? Psi I mean if i do a t at sending unit.

I really believe the potential cooling capabilites of the BPD cooler cannot be achieved due to the electric clutch and what determines its operation. I really think a hydraulic clutch is needed. I dont think Ive ever heard my fan kick on to be honest.

 

The minimum engine oil pressure specifications are 82.7 kPa (12 psi) at 700 rpm, 165.5 kPa (24 psi) at 1,200 rpm and 310.3 kPa (45 psi) at 1,800 rpm with the engine at operating temperature. Low or no pressure could be caused by the oil pressure regulator, gerotor oil pump or an internal lube oil pressure leak.

Pressures will be higher when cold.

 

The 6 oh only disappoints more over time. The fan just ate or nicked the clutch plug/wire and popped a hole in the radiator. Brought Snap on scanner and had fan at 100% duty cycle to see If it could even hear it. I was on my way to home depot for a t and some fittings to test base oil pressure. Is what it is. After radiator, 7.3 fan clutch, BPD water pump ill get back to original issue. All with 34k on the clock. Could be worse, I could need another transmission. Did that at 19k