Low Oil Pressure While Driving Rb25det

[R33 0wnerrr]

Hey guys,

My rb25det today while i was driving along was reading fine oil pressure on the factory gauge...about 5 on the cold start...then about 3.5-4 when i was cruising at 100 on the motorway at about 2800rpm...

But on the trip home it was only reading just a tiny bit over 2 on the gauge....no matter how fast i went...and it idles at just under 2...

It seems to be doing this randomly on and off lately...

So my question really is wondering if the oil pump is on its way out? its running a standard rb25det oil pump...its done nearly 140,000ks

I am doing the car serious damage to the bottom end or any other parts starving it of oil driving it like this arent i? is there any method of checking that its the oil pump or to check what it is causing this?

Thanks guys...any help would be appreciated..and yes i did search

[Granthem]

9 times out of 10 it is not an oil pressure problem, but an oil pressure sender issue.

Go to nissan and order a new sender order first

[bubba]

Does the light come on? if that comes on you really have to worry.. otherwise, the gauges/sender are notorious for being dodgy.

Get a quality electric oil pressure gauge and then you will know exactly what's going on.

[R33 0wnerrr]

  bubba said:

Does the light come on? if that comes on you really have to worry.. otherwise, the gauges/sender are notorious for being dodgy.

Get a quality electric oil pressure gauge and then you will know exactly what's going on.

Na it doesnt come on...going to try get a gauge tomorow...might aswell use this as an excuase to get a oil filter relocation kit while im at it

[bubba]

Ahh now that's the true spirit of car modification!

[tridentt150v]

Mine has done this as well, but I didn't care because I had an AM gauge that told me OP was OK. And strangely enough, the factory oil pressure gauge eventually came good and han't done it again [probably killed it by saying this out loud now...damn].

[Granthem]

  bubba said:

Does the light come on? if that comes on you really have to worry.. otherwise, the gauges/sender are notorious for being dodgy.

Get a quality electric oil pressure gauge and then you will know exactly what's going on.

That said, by the time the light is on, the damage is done. It needs nearly no pressure for the light to come on.

You have done the right thing OP, keep an eye on it. But i reckon a mechanical gauge will show its just a faulty sender

[bubba]

Please don't suggest he use a mechanical oil pressure gauge.

Even a cheap electric gauge is far superior than running a capillary full of oil into your cabin.

[Granthem]

  bubba said:

Please don't suggest he use a mechanical oil pressure gauge.

Even a cheap electric gauge is far superior than running a capillary full of oil into your cabin.

Whatever floats his boat I guess. Mech/Elec. Still involves dicking around with lines and or wires.

Maybe he likes oil sprayed on his interior

[tridentt150v]

Actually ther ones that you used to be able to get that were oil filled behind the viewing glass = so the gauge range and needle is swimming in oil - always looked very trick. But yeah electronic these days is the go, no charisma, but no oil over the carpet either.

[bubba]

  tridentt150v said:

Actually ther ones that you used to be able to get that were oil filled behind the viewing glass = so the gauge range and needle is swimming in oil - always looked very trick. But yeah electronic these days is the go, no charisma, but no oil over the carpet either.

They weren't exactly oil filled, but some sort of silicon fluid, the point was to dampen any needle fluctuations so as to give a more accurate reading.

[zephyro90]

so if the light turn on it means the oil pump is busted? the engine may go as well?

Edited April 6, 2010 by zephyro90

[tadrosone]

so what should oil pressure be at? because i have the same problem. cold start around 4 on the gauge and once its warmed up hovers in between 2 and 4.

[geraus]

i would like to know the same thing

[R33 0wnerrr]

If yours hovers around 2-4 while driving warm..im sure thats normaly what it should be,

Mine wasnt going over 2 while cruising on the motorway or watever revs i gave it, but this chops and changes everytime so ill post a reply when i get my oil pressure gauge..as soon as money permits!

Btw i would be interested to know if the oil light does come on if a pump is stuffed or stuffing up...not if your engine has no oil haha

[zephyro90]

i think mine started when i connected a relocator kit. but i added an extra 1li of oil.

[Wheezy]

  bubba said:

Does the light come on? if that comes on you really have to worry.. otherwise, the gauges/sender are notorious for being dodgy.

Get a quality electric oil pressure gauge and then you will know exactly what's going on.

QFT!

[Granthem]

  R33 0wnerrr said:

Btw i would be interested to know if the oil light does come on if a pump is stuffed or stuffing up...not if your engine has no oil haha

The light comes on when there is no oil pressure (or very very low) so it will come on when you have no oil OR if your pump shits itself

The standard nissan oil pressure recommendations can be found on this site, just do a search. Either way, the standard acceptable figures are lower then what 99% of skyline guages show

[cr4ig0]

I'm having a similar problem, my car has 150,000 and each day the car is running less pressure (went from 3.5 to 2 to 1.5 and this morning i noticed it on 1) I'm pretty concerned about something damaging like oil pump especially since the high km's.

I read above that its probably the gauge but will the gauge still read okay only lower? When i boost it moves up to 4 on the gauge but on idle or cruise it will drop again.

[paulr33]

on light cruise / driving at 100km/h i would expect 2 kgcm2 oil pressure

my 220,000 rb25 with old oil in it has this pressure and its reasonble

when cold it will peak past 4kgcm2 and slowly decay to 2 when warm

1 kgcm2 at idle is too low

if oil pressure is critically low, oil pressure idiot light comes on

if this comes on during heavy load id say your engine is toast

if it comes on at idle, check the guage, and try an external tester/reader/mechanic