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Hey guys just noticed the other day my oil pressure is lower than usual... On the gauge, when at idle and warmed up i originally had about 3.5 kg/cm2 now i only have just over 1 kg/cm2. When the motor is reved above 2500 it goes up to almost 4kg/cm2 where as before it would got to 5kg/cm2. Using nulon nulon 10w40 engine oil...

has anyone had this issue?

What do your gauges read...?

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im having the same issue 25GTV,

use to sit on 2 when warm, sometimes it drops down to 1 or just below it.

after awhile it may go back to 2 or it may not.

i dunno whats wrong with it, maybe a faulty sender unit, hopefully not an actual problem with oil pressure.

im about to install a aftermarket oil pressure gauge with new sender so see how that goes.

oil pressure drops when the car idles, makes sense cause your engine isn't working much during idle.

Heat makes liquids expand to, so if your engines cold there shouldn't be as much pressure.

As oil increases in temperature the viscosity decreases (ie the oil becomes "thinner") and the oil pressure drops. You will have MORE pressure when the car is cold because the oil is thicker.

When mine is cold, it reads 4 at idle and maxes it when reved past 2k.

When it is warm, it sits around 3 at idle andgoes to about 5 in the higher rpm.

If you're worried, get a mechanical gauge and bolt it on under the hood, give the car a quick rev and see what it says.

Before anything, check the oil level.

im having the same issue 25GTV,

use to sit on 2 when warm, sometimes it drops down to 1 or just below it.

after awhile it may go back to 2 or it may not.

i dunno whats wrong with it, maybe a faulty sender unit, hopefully not an actual problem with oil pressure.

im about to install a aftermarket oil pressure gauge with new sender so see how that goes.

yeah mine used to do that, hasnt done it since being on the Martini Racing 5w50 oil tho :down:

Mine sits at 5kgcm and a bit cold @1100rpm and 2kgcm hot@ 800rpm and everywhere between 2kgcm and 6ish dependent on RPM and engine temp.

I'm using 10-40 Nulon full syn fast flow?-quick flow? whatever and Nissan OE oil filter.

I'm not to happy with the in between slow rev chugging around pressure which is showing between 2kgcm and 3.5kgcm (hot) in the 1000-2500rpm range, this is only 28.8 to 51psi in the good ole imperial measure.

I did however have a Ford Maverick -AKA Nissan GQ Patrol- which had a very similar looking oil pressure sending unit and which told a similar story, until it died after which it showed nothing til it was replaced , so I'm thinking (and hopeing) a lazy sending unit. :banana:

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