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hey guys/girls,

ive noticed recently that when i start my car (cold starts) that the oil gauge needle shoots straight up to 8. now after a while of idling the needle slowing goes down to 4. what is odd is that when i accelerate the needle goes slowing upwards towards the 8 on the oil guage, other times it would just stay on 4. but when i decelerate and slow down then the needle goes down to 2 but creeps back up again towards and stays at 4 when i accelerate. i dont think this is normal, as i dont recall the needle ever fluctuating up and down before. if i remember correctly, on cold starts the needle stay at 0 until it warms up then goes to 2 on the gauge and not often 4. am i being paranoid or is their something wrong??

any help is much appreciated,

duc.

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I thought that it should be higher when cold as the oil is more viscous when cold and harder to push, then as it gets up operating temp the viscosity get lower so easier to push, then at idle the oil pump isnt pumping much so the preasure drops...my car does the same thing so these are my assumptions, feel free to correct me

Normally it'll be higher when it's cold e.g. you first start the car, it'll go up to about 6ish.. than when warm settles down to about 2.. when accelerating it'll tend to go up to 4 - not much higher.. should sit on 2 when idling though and warmed up.. it changes with RPM though - higher the RPM the higher the oil pressure..

by the sounds of things its normal. after owning the car for 3+ years, its only now that ive noticed the needle fluctuating in response to throttle reponse and oil temps is nothing out of the ordinary. thanks for reassuring me.

Yes, this is normal. The 8 is a bit high but the Skylines are renowned for their oil guages playing up. I would run an engine flush through at your next oil change just in case you have the oil pressure relief valve sticking in the oil pump. Other than that, the guage is operating completely normally. It should go up when you accell and go down when you decel. The needle should sit on around 2 when it's warm at idle and go no higher than around 7 at about 6000 rpm.

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