Wierd Oil Pressure....

[nissan200sx.dk]

Hi all.

Heres the thing... My oil pressure on my newly rebuilt rb25det s1 engine is wierd... happended suddendly.

when cold 100psi at idle, when 180F its juuust under 25 psi idle 800 rpms. This is good as far as i know.

I will use a scale from 1 to 10 to simplyfy "acceleration" here in my example. 10 is full throttle

But! When accelerating, especially in first and second at say 4 ish, oil pressuere suddenly fall of! it just drops, both my std oil pressure sensor and my autogauge oilpressure is doing it. shift into 3rd an give more throttle, accelerting at say 6, I can feel mere acccel. it doesnt drop of, I can floor it, it stays up, sometimes dropping a little..

I have just run in the engine over 5000 km, and have given more and more gas and revs. havnt noticed anything like this! and have accelerated on full throttle, just one morning this issue!!! Im not 100% sure, but i THINK it was after a night with alot of rain and wind.

Have tryed WD40 on my connections.

My worst thougt is this is something mechanical... If oil pump is on its way does it do this?? what mechanical thing could do this?

If i just rev the engine no drop of in oil pressure. Have also tryed filling 1 liter oil more on it.. no change.

Can anyone help?

[Yawn]

So it happens when its on mid-throttle?

Youve probably already done this but checked your oil-level? Or else it may be the oil pump.

Did you get a new one put in when the engine was rebuilt?

[nissan200sx.dk]

no i did not get a new one, the old one was checked. and was fine.

but you recon its a mechanical issue not an electrical sensor issue?

[tridentt150v]

oil pick up problem maybe, so oil starvation, but I thought the pickup was to the rear anyway. What power are you making?

[nissan200sx.dk]

its a sudden thing this issue!... it happend over night...

and have given much more gas than what it takes to make the pressure drop now..

but, im fitting a mechanical oil pressure gauge, and will see if pressure drops.

[nissan200sx.dk]

Well, the oil pressure is something mechanical... hooked up a regular gauge and it does the same.

So any suggestions were ill go fróm here?

Will try and remove oil pan to check the oil pickup. Anything else while im there?

[Guilt-Toy]

dont risk it with the oil pump, i nearly lost my forged engine because i was using my old pump.

Got a N1 pump and now its fine. if anything it has too much oil pressure. We changed mine with the engine still in the car. was a pain in the ass to do too.

[nuclear_skyline]

So it happens when its on mid-throttle?

Youve probably already done this but checked your oil-level? Or else it may be the oil pump.

Did you get a new one put in when the engine was rebuilt?

Have you checked your oil level??? If the problem is associated with acceleration, my first check point would be how high my oil is....

[femno]

Hows about you take it back to where it was rebuilt and get someone who knows what they are doing to look at it?

[nissan200sx.dk]

Oil lvl has been checked, before I tryed 1 more liter oil. no change.

Its built by myself...

Have a slight feeling it may be my oil pickup, its in a s13, so oil pan is pretty close to the road..