When I got the car 10 months ago, the oil pressure gauge just moved from cold and then after 10 mins would settle back to zero and would not move again until another start from cold then the same would happen. :confused1:

About 6 months ago I got a Stack oil pressure gauge in bar for the 3 pod pillar mount, this works a treat and is connected to the sandwich plate.

At the time of fitting I had the stock guage sender cleaned out, which I thought made no difference at the time as the same occurred. :tt1:

Took the clocks apart to fit the blue smd odometer illumination and I was fiddling with the oil pressure needle once more.

Now, I can only call it a coiled spring calibrator is it? thats sits to return it methinks, this was all beat up and just resembled thin metal ribbon, played with it briefly whilst flicking the needle and seemed to be happy with the position and action of it, decided to trim it and then it seemed to go all wrong so I removed it completely, it was all wrapped round crudely anyway, the needle now moves completely freely.

Refit the clocks and went for a spin.

As usual it moved to about 45psi on start up, drove a bit more until fully warm, It now works :thumbup1: although not very accurately as I expect they never were great.

At idle it drops to about 20psi and then at 3000rpm is showing at around 50psi, never as yet as it gone above the 60psi centre mark.

As 1bar is roughly 15psi and my aftermarket gauge is perfect and goes to even 6 bar at high revs/start up, it shows how inaccurate the stock gauge is or mine in particular? please let me know? :helpsmilie:

When I turn the engine off the needle stays where it is, as soon as I put the ignition back on the needle immediately returns to zero, on start up the needle is back in motion again, all this normal behaviour? :confused:

But eh, it now works and moves about which delights me, although it does move at it's own slow rate and not instant like the rev counter, it's like there is a satellite delay to it :whistling:

So is the lesson remove the metal spring thingy!! :thumbup:

Appreciate your efforts mate, but the stock oil gauge is generally fine, its the sender under the engine that goes faulty and cleaning it out makes no difference, the only solution is to replace it (£85ish for new OEM). The problem can be blockage with dirty oil, but generally after 20yrs or so its the mechanism inside the sender that wears to failure.

The problem you described is really really common. I had it too, changed the sender and the gauge now moves and operates correctly and very speedy too.

I have not touched the sender at all in 6 months.

I think on mine the 'spring' was that mangled up for some reason it had got itself in such a position that it was braking the needle from moving. :no:

Once removed completely it had freedom again, albeit it reacts slow it seems, but this must be because this spring is now missing, best I can do unfortunately, can only conclude that my sender is fine.

Many thanks Craig for your response. :wink:

OK mate fair enough.

In answer to one of your questions...

 

When I turn the engine off the needle stays where it is, as soon as I put the ignition back on the needle immediately returns to zero, on start up the needle is back in motion again, all this normal behaviour?

 

...the answer is no. The needle should drop to zero when switching engine off, the spring that you have removed is probably designed to do that. Also would imagine the gauge will now be even more inaccurate because it was calibrated to work with the needle spring pressure. The needle on the boost and oil pressure gauges should not be able to move too freely (the speedo+rev needles do). The same applies to fuel and temp gauge.

They are under a slight tension. The speedo and rev needles are so free you can blow them round the dial!, but not the others.

 

And the question...

 

As 1bar is roughly 15psi and my aftermarket gauge is perfect and goes to even 6 bar at high revs/start up, it shows how inaccurate the stock gauge is or mine in particular? please let me know?

 

...It is yours. My car gauge reads around 3/4 deflection on cold start up which is around 90psi. This tally's with your 6bar aftermarket gauge reading and shows your stock gauge and/or sender unit is still not working correctly.

Edited August 29, 201015 yr by turbocraigy

Hope I'm not coming across as an arse, can some times read like that. I'm just trying to answer your questions and help you!!:)

 

I would still bet that your stock sender is faulting (they usual read OK with cold engine and fail when hot) and you may have accidently buggered your gauge. Hope not though.

JeffTT posted this interesting information sometime ago. I will copy and paste it. They you go....

 

Took one of the sensors apart years ago to determine exactly what it is that fails in them, yes the hole can get blocked but that would worry me that the oil has not been changed very often, the unit fits in the turbo oil feed!!

 

The unit is part Nissan high tech and part school project, oil pressure acts on a small diaphram, there is a small linkage that connected between the diaphram and an acting swing arm.

 

The swing arm via the diaphram moves in relation to oil pressure,the upper part of the swing arm makes an electrical connection via a brass rubbing strip on to a variable resister that looks very similar to the insides of an old scaletrix hand controller.

 

The section of track where the rubbing strip is infrequently sitting such as when the oil pressure is high ( when cold or higher revs) remain in good condition and so the rubbing strip makes a good contact and the gauge shows high pressure.

 

Once the oil warms up and the pressure drop to normal or the revs are much lower the rubbing strip is now in a highly used area of the track and this is the worn part, hence a bad connection and a poor gauge reading.

 

There is nothing to do except replace it, I have no idea of the quality of e-bay items but they do go for around £35 which is probably a better idea than a second hand one, but a new Nissan one alays returns everything to normal.

 

The unit was used on the Nissan Patrol I think and most likely Almera Gt etc.

 

Jeff TT

Edited August 29, 201015 yr by turbocraigy

Not an arse Craig just a t**t :tt2:

No joking aside, it is why I threaded as I just wanted exactly the info you have given me, so I thank you.

Given that at some point somebody as goosed up the spring, I have done the next best thing and at least it moves about and I can live with that, I do have an accurate aftermarket one to glance at.

You are probably correct the sender does have a fault and we know now that the needle as, two out two aint bad :whistling:

Thanks again :winkiss: