Jump to content
SAU Community

Fluctuating Oil Pressure

G Kanobi

By G Kanobi,
in R Series (R30, R31, R32, R33, R34)

 Share

Recommended Posts

G Kanobi Enthusiast

G Kanobi

Posted
Posted

Hey guys,

My cars been doing something odd lately. Oil pressure seems to be going up and down. I can't seem to find any pattern to it. Tried different driving situations and driving on hot/cold days. It either reads somewhere just under the 4, or only just about the 0, or some times reads flat 0.

I'm well aware I shouldn't be driving with this amount of pressure, but have had no choice this week. Probably done around 1000km's since this has been happening.

This said, the engine is still running, and seems to be okay.

I'd say about 70% of the time its been reading 0. 20% hanging between just above 0 and 1/4. And the other 10% just under 1/2.

The car is running rich, and idling high (fluctuating between 1,200RPM - 1,800RPM). I gave it an oil change hoping it was the broken down oil, but it seems to of had no effect.

ANY ADVICE would be greatly appreciate. I have no idea where to start with this problem. Faulty oil pressure sender unit perhaps?

Ideas??

Thanks heaps

Regards

Glen

Link to comment
https://www.sau.com.au/forums/topic/235459-fluctuating-oil-pressure/
Share on other sites
Beer Baron Grand Master

Beer Baron

Posted
Posted

just to make sure. you do realise that oil pressure goes up as reves go up, and goes down when revs go down right? so it's quite normal to see oil pressure at 1bar at idle, then 6 bar under high rpm. or even 8 bar+ if the engine is cold.

  • 8 months later...
bumble_bee Rising Star

bumble_bee

Posted
Posted

hey just a quick questions wer is the oil pressure sender unit located?

is there a fix or a way to clean it or anything?

i think mine mit b playing up.

for about a month now, ive notice my oil pressure sits on about 6-8 wen cold.. just under 8 wen driving.

and on about 3000rpms sits around 3.5?

this is on the stock gauge.

and on idle after some long drives it sits on 2.

is this normal? i swear it use to never be all over before. or that high when cold.

im running penrite 10-50 and a gen. nissan filter.

and it has been burning the oil abit now, i believe.

never use too.

but no smoke and no leaks.

also im running a new highflow hypergear atr28 g2 bush bearing turbo with speedflow line to the turbo.

and my engine done about 118,000k's

i did run motul 10-40 turbolight through wen i first fitted the turbo, which was a bout 100,000k's..

so i used it twice, but i reckon it ran better on penrite. thats y i went back.

was this a good idea?

but yeah. any ideas would be great.

thanks

hypergear Grand Master

hypergear

Posted
Posted

I've been importing cars for a number of years I don't think most of them work probably due to its age. Some of them don't even move. As long as the car's driving good you don't really have to worry about that gauge much.

SECURITY Grand Master

SECURITY

Posted
Posted

i dont think the fault is with the sender because when you're reading actual low pressure your engine light comes on.

i think the fault is with the gauge - when i took apart my gauge in the dash there was a resistor on the circuit board that had looked like it had blown, there was also traces of carbon around the plastic, if i find the picture i took ill post it up.

bumble_bee Rising Star

bumble_bee

Posted
Posted
i dont think the fault is with the sender because when you're reading actual low pressure your engine light comes on.

i think the fault is with the gauge - when i took apart my gauge in the dash there was a resistor on the circuit board that had looked like it had blown, there was also traces of carbon around the plastic, if i find the picture i took ill post it up.

oh ok.. yeah no lights appearing.

mayb im just worring over nothing.

car is driving fine..so yeah

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
 Share
Go to topic listing


  • Similar Content

  • Latest Posts

    • Milkmun
      The FD RX7 is the best looking 90's JDM car

      By Milkmun · Posted

      Lucky man, who owns it in the family? Any pics? 
    • Kinkstaah
      Mistakes were made, my R34 Story

      By Kinkstaah · Posted

      The engine stuff is Greg Autism to the Max. I contacted Tony Mamo previously from AFR who went off to make his own company to further refine AFR heads. He is a wizard in US LS world. Pretty much the best person on earth who will sell you things he's done weird wizard magic to. The cam spec is not too different. I have a 232/234 .600/603 lift, 114LSA cam currently. The new one is 227/233 .638 .634. The 1.8 ratio roller rockers will effectively push this cam into the ~.670 range. These also get Mamo'ified to be drilled out and tapped to use a 10mm bolt over an 8mm for better stability. This is what lead to the cam being specced. The plan is to run it to 6800. (6600 currently). The Johnson lifters are to maintain proper lift at heavy use which is something the LS7's supposedly fail at and lose a bit of pressure, robbing you of lift at higher RPM. Hollow stem valves for better, well everything, Valve train control. I dunno. Hollow is better. The valves are also not on a standard valve angle. Compression ratio is going from 10.6 to 11.3. The cam is smaller, but also not really... The cam was specced when I generated a chart where I counted the frames of a lap video I had and noted how much of the time in % I spent at what RPM while on track at Sandown. The current cam/heads are a bit mismatched, the standard LS1 heads are the restriction to power, which is why everyone CNC's them to get a pretty solid improvement. Most of the difference between LS1->LS2->LS3 is really just better stock heads. The current cam is falling over about 600rpm earlier than it 'should' given the rest of my current setup. CNC'ing heads closes the gap with regards to heads. Aftermarket heads eliminate the gap and go further. The MMS heads go even further than that, and the heads I have in the box could quite easily be bolted to a 7.0 427ci or 454 and not be any restriction at all. Tony Mamo previously worked with AFR, designed new heads from scratch then eventually founded his own business. There he takes the AFR items and performs further wizardry, CNC'ing them and then manually porting the result. He also ports the FAST102 composite manifold: Before and after There's also an improved racing crank scraper and windage tray. Helps to keep oil in the pan. Supposedly gains 2% power. Tony also ports Melling oil pumps, so you get more oil pressure down low at idle, and the same as what you want up top thanks to a suitable relief spring. There's also the timing chain kit with a Torrington bearing to make sure the cam doesn't have any thrust. Yes I'll post a before and after when it all eventually goes together. It'll probably make 2kw more than a setup that would be $15,000 cheaper :p
    • MBS206
      Can't put strut back

      By MBS206 · Posted

      Because the cars wheels are on blocks, you slide under the car.   Pretty much all the bolts you touched should have been put in, but not fully torque up.   Back them off a turn or two, and then tighten them up from under the car with the wheels sitting on the blocks holding car up in the air.
    • MBS206
      Can't put strut back

      By MBS206 · Posted

      Yes. Imagine you have the car on the ground, and you mine away all the ground under and around it, except for the area directly under each individual wheel. That's exactly how it'd look, except the ground will be what ever you make the bit under each wheel from
    • GTSBoy
      Can't put strut back

      By GTSBoy · Posted

      Yes, if you set the "height" right so that it's basically where it would be when sitting on the wheel. It's actually exactly how I tighten bolts that need to be done that way. However....urethane bushes do NOT need to be done that way. The bush slides on both the inner and outer. It's only rubber bushes that are bonded to the outer that need to be clamped to the crush tube in the "home" position. And my car is so full of sphericals now that I have very few that I need to do properly and I sometimes forget and have to go back and fix it afterwards!
×
×
  • Create New...