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Oil - Pressure Variance On Acceleration?

Penfold

By Penfold,
in Engines & Forced Induction

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Penfold Rising Star

Penfold

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Hi,

Had my engine rebuilt about 9000km ago. Lately I have been noticing that the oil pressure guage fluctuates more than it used to. At idle, low accelaration it sits on just above the 2 (kg/cm2) but on acceleration it goes up to just below the 4 (kg/cm2) - it moves vary quickly. I know before the rebuild the pressure did not vary that much. I do have a remote oil filter too and the oil temps seem normal.

Is this ok?

Cheers,

Pen

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  • 10 years later...
samuri Rising Star

samuri

Posted
Posted

 

My 15 years driving a non turbo gts always  had a pressure around 3.9kg/cm²,

now however it's moving between 3-8 and 1.9 ,once warmed up. the range depends on the revs .

Pretty much like Penfolds description.

Whats happened to create this variation.

I never saw it at 1.9

At what point is low oil pressure  a problem. what specification or figure is a concern

btw .have had a blown head gasket and bent number 6 corned replaced but this shouldn't be related

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GTSBoy Grand Master

GTSBoy

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Trust the factory gauge at your peril.  It is probably not reading correctly.  They are shit.  Mine reads almost zero at hot idle.  The oil pressure is actually fine.  I don't even look at it.  Haven't for 10 years.

If you want to know what the oil pressure really is, you had best hook up another gauge and take the car for a drive/dyno run.

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samuri Rising Star

samuri

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4 hours ago, samuri said:

 

My 15 years driving a non turbo gts always  had a pressure around 3.9kg/cm²,

now however it's moving between 3-8 and 1.9 ,once warmed up. the range depends on the revs .

Pretty much like Penfolds description.

Whats happened to create this variation.

I never saw it at 1.9

At what point is low oil pressure  a problem. what specification or figure is a concern

btw .have had a blown head gasket and bent number 6 corned replaced but this shouldn't be related

 

3 hours ago, GTSBoy said:

Trust the factory gauge at your peril.  It is probably not reading correctly.  They are shit.  Mine reads almost zero at hot idle.  The oil pressure is actually fine.  I don't even look at it.  Haven't for 10 years.

If you want to know what the oil pressure really is, you had best hook up another gauge and take the car for a drive/dyno run.

So the oil pressure sensor is not the problem in your experience ,just the gauge. How can this be determined?

What brand /model after market  do you recommend or stay away from.

thanks

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GTSBoy Grand Master

GTSBoy

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4 hours ago, samuri said:

So the oil pressure sensor is not the problem in your experience ,just the gauge. How can this be determined?

I didn't say "gauge" meaning "only the gauge".  I said "gauge" meaning "all the parts of the factory gauge", including the sensor. Sensor/gauge.  Doesn't matter which one of them is f**ked.

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