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Oil Pressure Problems

Benno31

By Benno31,
in Engines & Forced Induction

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Benno31 Experienced

Benno31

Posted
Posted

Gday All,

As of last night my oil pressure guage will read normal and then randomly and independent of rpm, will drop to almost 0. When the engine rpm is increased the pressure will rise but not as much as normal. It is reduced by about half of the normal readings at any given rpm.

I am wondering whether it is a voltage issue or guage issue or worst of all, an actual oil pressure problem.

Any insight into this problem is appreciated. Car is a 1989 GT-R.

Cheers,

Ben.

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James_03 Mentor

James_03

Posted
Posted (edited)

colar is most likely stuffed on the pump, again take it to a mechanic and get an independant reading done by removing the sender, but I would be betting on it being the colar.

yes it could still be the sender of cluster itself but I myself wouldnt be taking that risk.

I did once and I ended up rebuiling the motor.

Edited by James_03
TurboX Mentor

TurboX

Posted
Posted

Damn I just replaced the crank and rods and the Oil press sender (from another RB) and its doing the same thing and reading all over the place.

I thought it was just the gauge before but the clattering noise was a bit of a giveaway as well so expected problems.

Found out it was the countersunk screws in the back of the oil pump had come right out!

So dont think its the sender unless proven, but hopefully this time it is!

d00dz Grand Master

d00dz

Posted
Posted
I think I will avoid running the engine completely to be safe. can't afford a rebuilt right now.

Thanks heaps for the replies. You guys are lifesavers.

Yea I know the feeling. Dont know whats wrong with it and kinda hope its not anything bad. Seeing it read 0 is scarey. Esp when you dont or not plan for rebuilds. :wave:

MerlinTheHapyPig Mentor

MerlinTheHapyPig

Posted
Posted

when my gauge reads zero... my mental argument is that the red warning light doesn't come on, so not to worry. When that light starts coming on, then i'll worry!!

My guage has been playing up for roughly a year, and i've been drifting the car, almost weekly. So, if something was wrong with the oil pump, i figure my engine would have blown itself up a long time ago

Jolinator Proficient

Jolinator

Posted
Posted (edited)

red light and gauge are independant, when the red light comes on you have no oil pressure. i have similier issues, mine always reads low, but i have seen it drop to zero when i came to a stop once, also it moves under heavy breaking.

Edited by Jolinator
Benno31 Experienced

Benno31

Posted
  • Author
Posted

Well, good news. It is the sender unit. The car had 90PSI at cold idle.

Now to find a cost effective replacement, I hear the nissan genuine units are $220 odd.

A big thanks to Dan (3lit3 32) for taking the time to drive 45 minutes to help me out.

jantolis Proficient

jantolis

Posted
Posted

For some reason and for the first time in about 3 weeks, the guage seems to be working. It was reading almost zero after driving for a while but yesterday it was at 6 when starting then made it's way down to 2 and stayed there until i revved it and then it went up and then back down to normal.

Hopefully it stays working but i won't count on it.

The Alchemist Collaborator

The Alchemist

Posted
Posted

I replaced my sender unit with a new one, had similar problems, and also connected a mechanical gauge and compared the results to the original dash mounted GTR gauge.

Interesting results.......

While the mechanical gauge can be reading a steady figure say 45psi the Nissan gauge can vary between 2 to 3 KG/cm3 depending on its mood. Also at idle the mech gauge reads 30PSI rock steady the nissan gauge still reads high at around 40psi equivilent. At 4000rpm the mech gauge is up around 80PSI the nissan gauge still reads about 4 kg/cm3. So even with a decent sender the Nissan gauge is really a indicator that you have oil pressure, how much exactly can only be sorted with a good mechanical gauge fitted.

Mike

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