Jump to content
SAU Community

Recommended Posts

Hi there to all sau members,i am new in the scene on here in the forums but i would love to know if someone could please enlighten me on why my oil pressure gauge is so low,i will explain first... i did a service on my car last week changed spark plugs put new oil and oil filter etc etc the only thing that changed was the oil i used motul turbo light last time and it is 10w 40 and this time i used motul 8100 5w 40 and since this change i have noticed my gauge at idle drops down to near 1 bar and when i accelerate it goes up as normal why would this happen?? but on the other hand my car is going better than it has in the past lol,i have checked for oil leaks and there is nothing so this has got me stummped... :)

any help would be much appreciated

cheers guys

Brad :blink:

Link to comment
https://www.sau.com.au/forums/topic/337511-oil-pressure-gauge/
Share on other sites

yep you are correct and im wrong, oil pressure (at least for ECR33 RB25DET) is

1.1kgcm2 at idle

3.5kgcm2 at 2000rpm

5.6kgcm2 at 6000rpm

i always assumed it was meant to be 2.0kgcm2 at idle

ive never seen near 1kgcm2 at idle on my car, its always 2kgcm2 at idle

but i do put in 5l each time and usually go for 5w40 but rb25 + 230k on the ODO

Mine sits at about 3.5 at idle and 4 @ 2,000 rpm reaching a max of close to 5 when you put your foot down. That makes it sound as if perhaps last time it was serviced that used too thick of oil....thoughts?

yep you are correct and im wrong, oil pressure (at least for ECR33 RB25DET) is

1.1kgcm2 at idle

3.5kgcm2 at 2000rpm

5.6kgcm2 at 6000rpm

i always assumed it was meant to be 2.0kgcm2 at idle

ive never seen near 1kgcm2 at idle on my car, its always 2kgcm2 at idle

but i do put in 5l each time and usually go for 5w40 but rb25 + 230k on the ODO

Those figures are based on the recommended oil from Nissan. And the 5W / 10W figures are irrelevant to this - they are cold start viscosities.

Different oils behave differently when warm, under shear. It's not unlikely that 2 supposedly identical oils (both 40s) should give different pressure readings under the same engine conditions.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • If you are keeping the current calipers you need to keep the current disc as the spacing of the caliper determines the disc diameter. Have you trial fitted the GTS brakes fit on a GTSt hub or is this forward planning? There could be differences in caliper mount spacing, backing plate and even hub shape that could cause an issue.
    • Hi there I have a r33 gts with 4 stud small brakes, I'm going to convert to 5 stud but keep the small brakes, what size rotor would I need?
    • First up, I wouldn't use PID straight up for boost control. There's also other control techniques that can be implemented. And as I said, and you keep missing the point. It's not the ONE thing, it's the wrapping it up together with everything else in the one system that starts to unravel the problem. It's why there are people who can work in a certain field as a generalist, IE a IT person, and then there are specialists. IE, an SQL database specialist. Sure the IT person can build and run a database, and it'll work, however theyll likely never be as good as a specialist.   So, as said, it's not as simple as you're thinking. And yes, there's a limit to the number of everything's in MCUs, and they run out far to freaking fast when you're designing a complex system, which means you have to make compromises. Add to that, you'll have a limited team working on it, so fixing / tweaking some features means some features are a higher priority than others. Add to that, someone might fix a problem around a certain unrelated feature, and that change due to other complexities in the system design, can now cause a new, unforseen bug in something else.   The whole thing is, as said, sometimes split systems can work as good, and if not better. Plus when there's no need to spend $4k on an all in one solution, to meet the needs of a $200 system, maybe don't just spout off things others have said / you've read. There's a lot of misinformation on the internet, including in translated service manuals, and data sheets. Going and doing, so that you know, is better than stating something you read. Stating something that has been read, is about as useful as an engineering graduate, as all they know is what they've read. And trust me, nearly every engineering graduate is useless in the real world. And add to that, if you don't know this stuff, and just have an opinion, maybe accept what people with experience are telling you as information, and don't keep reciting the exact same thing over and over in response.
    • How complicated is PID boost control? To me it really doesn't seem that difficult. I'm not disputing the core assertion (specialization can be better than general purpose solutions), I'm just saying we're 30+ years removed from the days when transistor budgets were in the thousands and we had to hem and haw about whether there's enough ECC DRAM or enough clock cycles or the interrupt handler can respond fast enough to handle another task. I really struggle to see how a Greddy Profec or an HKS EVC7 or whatever else is somehow a far superior solution to what you get in a Haltech Nexus/Elite ECU. I don't see OEMs spending time on dedicated boost control modules in any car I've ever touched. Is there value to separating out a motor controller or engine controller vs an infotainment module? Of course, those are two completely different tasks with highly divergent requirements. The reason why I cite data sheets, service manuals, etc is because as you have clearly suggested I don't know what I'm doing, can't learn how to do anything correctly, and have never actually done anything myself. So when I do offer advice to people I like to use sources that are not just based off of taking my word for it and can be independently verified by others so it's not just my misinterpretation of a primary source.
    • That's awesome, well done! Love all these older Datsun / Nissans so rare now
×
×
  • Create New...