DriftDamage

So I've been trying to figure out why my oil pressure is too high. This just recently started up. It has always been a bit high in my opinion around 40-90psi but only recently skyrocketed to 120psi at start up and idle.

I use Mobil 1 15w50 oil and K&N oil filters. I'm sure the weight adds to the higher pressure but 120 psi seems ridiculous. Unless I allow the engine and oil to warm up for a while to get the oil temp up to around 150-200 degrees F, the psi will max out on my gauge past 150psi which I'm sure is not good for the engine.

This 120 just happened within the last few days and I just did an oil change right now thinking it could have been a clogged filter. What would be the next best course of action to take? What kind of damage could I be looking at if I don't fix this soon?

Any help would be greatly appreciated.

e1_griego

Why are you running 15w-50?

DriftDamage

Because I live in the desert and my car sees a lot of track time plus daily driving.

Mikester

LOL this was my question. In my non-ASE certified opinion, switching (and staying) to 10W30 would have been step one.

SR's are designed to operate in all extremes... changing recommended viscosity doesn't necessarily ensure better protection- quality oil & regular oil changes & preventative maintenance on the other hand will.

I'd definitely check the oil filter, housing and crankcase ventilation system... as well as the turbine oil feed/drain and anything/everything else able to be gotten to without breaking the motor down... Hopefully the problem will be obvious.

If high temps are a worry, an oil cooler system with a thermostat would be much more effective than thicker oil. NTM an oil cooler increases oil capacity

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hobbs

I would also check your oil pressure sensor, sensors are known to go bad if they are mounted to the engine block.

Also when I was using a VE oil pump I would see 124psi of oil pressure at cold start in the winter with 10w30, although once it warmed up I would see around 25-30 psi at idle.

Z28ricer

Its good that even without ASE cert you can manage to read the oil cap on an engine, or look up the standard oil fill.


However since you've done SO much research about what oil to use, i'm surprised you've never managed to fully research what OEM's suggest, other than finding the one size fits all don't know where the car will be shipped standard fill.


This particular chart is from a MB, you'll find similar for corvettes, and even nissans, though I didn't feel like taking the time to chase down the Nissan listings to spoon feed you.





Porsche ?





Yet another







The common denominator, going up for areas that see high ambient temperatures. Sure its not going to destroy a car that runs 5-30 to drive to FL and back, but choosing your oil based off of the climate the vehicle is in, is clearly the better procedure, rather than your preached THIS IS WHAT NISSAN PUT IN IT THEY KNOW BEST THIS OIL IS BEST

Drift_FX

i also run 15w50, but im using e85 witch has poor lubrication qualities compaired to gasoline, additionally my car does not see cold climates...

Mikester

Jesus dude- Would a hug make you feel better? I hope you realize that your little rant had little/nothing to do with the overall intention of the topic...

If you have something to contribute to this guy's oil pressure woes, by all means contribute.

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Z28ricer

You say he's using the wrong oil, I disproved your theory, contributes by making sure you don't point him in the wrong direction. So I guess your little rant had little to do with the topic huh ?


His oil pressure sender or wiring is likely messed up, I didn't mention it because its already been mentioned.

fliprayzin240sx

I think his choice of oil is too thick considering its winter time and ambient temp across the US other FL is cold as shit. Personal experience and personal preference speaking, I only run 15w50 in the summer when I see ambient temps of 90 and above. It just takes too damn long for that oil to get to temp and start flowing. I usually kick my winter oil down to 10w30 or 10w40

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Z28ricer

Apparently it is cold there, however still not outside the temperature range for an SR based on the FSM using 15-50 ( -4F-104+)

My original comment was mainly directed at the repetitive regurgitation of "Mikester" trying to insist that the standard common oil fill is the best choice for an SR no matter what, and his insinuation that the SR is magically designed to operate at all temps with his suggestion on oil, rather than the climate based suggestions of the OEM.


Again referencing the FSM, the oil is a factory suggested viscosity for the temperature where he's at, and i'd look to the gauge setup, it isn't very hard to get an air pressure gauge, a T fitting and an air compressor to connect his gauge as well as a reference gauge to compare what's going on.

DriftDamage

Thank you to those who actually tried to contribute solutions or ways to check what could be wrong instead of insulting my oil choice which is within the FSMs specifications for my area and it's general temperature.

Even in the coldest of temperatures here for the past few years my oil pressure wouldn't go above 90 psi until just this weekend hinting it is a clog or some other issue. Certainly switching to a more winter friendly oil would decrease my suddenly high 120psi oil pressure but it still wouldn't fix whatever is causing this sudden spike. So regardless of how you insult my choice or defend yours it doesn't contribute anything productive to solve my issue.

So please if you have nothing to contribute besides where you stand on oil choice then please do not comment here as I am trying to resolve a problem.

Z28ricer

So back to determining the issue...


What brand is the gauge ?

What type is the gauge ? Mech ? Elec ?

If electric have you checked the wiring ?

Do you have a compressor and can you go ahead with the test I suggested ? If your sending unit is already 1/8" NPT then it isn't too hard to connect it up with a T and a reference gauge to a compressor, you'll know quickly if you're actually getting 120 off the engine or if its in your gauge setup.

DriftDamage

New oil filter and the housing around it seemed clear of any obstruction. Where is the crankcase ventilation system?
I'll prob drain all the oil and check the oil lines this weekend as you suggest.

Is there another way to check oil pressure? I am using a Prosport oil pressure gauge. It's digital and so I could see how that could be faulty. I will check the wiring but somehow I have a small feeling it's not the gauge.

DriftDamage

My gauge is a digital one. Is there another way to do this?

mechanicalmoron

For what it's worth, the only part that the high oil pressure should wear is the pump, I'm pretty sure it will only improve how every other part functions. Better bearing protection, for sure. (maybe it could hurt a turbo, because I have no fucking clue how their bearings work - but I don't think so, if it's designed well)

It's high because you have thick oil. Thick oil resists being forced through tiny gaps harder than thin oil, and, theoretically, can resist more force before metal/metal contact, as it's under more pressure/there's more of it being forced in there at once.

The reason it shot up is because of the season change, it got colder. Cold oil is thicker, and cold 15 weight is thicker than hot 50 weight.

The reason you'd use thick oil is for excessive clearances in your motor, or, to resist heat-related thinning (the thick oil shouldn't actually withstand any higher temps before perminant oxidation or burning occurs - it's made out of the same shit, only with longer polymer chain molicules to control the viscosity, that will probably actually wear out/shear faster/more delicately.), and thus a loss of pressure. Especially, wide gaps between the viscosity numbers on a multi-weight oil makes it break down faster, which is why race oil is often strait weight. If you don't want high oil pressure or don't feel comfortable with it, it's really simple..... choose the proper oil.

Simply living in a hot place doesn't mean you need super thick oil. Maybe if you like, lived in death valley or something? If you beat the piss out of the car in the heat for extended times, THEN you should worry about a thick oil - otherwise I don't see a reason to move up more than one grade (5/10w40) unless you have a motor that smokes.

I have a ka, but for reference, I run ungodly thick oil because of the condition of my rings and valve seals. I run 20w50, with a good amount of thickener added. Basically, it's as thick as the amsoil in my transmission.... I drive it, I drive it hard, I rev it high (sometimes, though it sort of makes me shit bricks sometimes), and it's been that way for years and 17k miles since I bought the car. I'm going to drive it on that motor till it won't drive another inch, and my compression has held steady..... it would be sort of hilarious, but I think I might make 300k on it. By comparison to my oil, yours is gentle. I'm sure lots of other people run 50w in SR's, and the 15w is much better than 20w for cold starts. Just let it idle a few minutes before you drive it, then go gently until your temp gauge comes up. IMO, anyway.... but I think you'll be fine. And if it worries you, just drop a weight, and I bet it goes to exactly normal.

You know, people shim their oil pumps valves and such, to get higher pressure, specifically for more protection for their high power engines... so...

Mikester

Z28riceguy:Pretty sure you should read my post again. If I can 'read an oil cap' and comprehend it (Nice catch, Captin O.) then I would hope that you could comprehend a bit more than you've shown. I clearly posted based on opinion (I think the word 'opinion' is even in there somewhere if you look hard enough)... which would theoretically make it clear that I have no credentials to back up anything I have to say. In other words- You haven't disproven anything because there was never anything to prove...

I've lived all around the world in all types of climates and beaten the living shit out of my cars. Unless what I owned was built well outside the scope of "OEM', whatever was 'on the cap' was what went into the gullet. Maybe I've just been lucky(?)

Does being so nasty bring you happiness? Lighten up.

OP: Nobody was insulting your choice of oil. Had I know that this would have turned out like this, I'd have stuck a little more closely to your issue too.

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DriftDamage

Prosport Premium. Elec. Just got back from checking and tracing the wiring. Looks fine to me, no frayed or crossing wires.

I guess i'll have to find a connection to check with a mechanical pressure gauge.

Mikester

There are lots of other things (like the sender as stated) that would be SO MUCH more likely than your crankcase ventilation system (PCV valve & line from valve cover 'tee' fitting to turbine inlet). I was just throwing that out there to make sure you didn't have any of that capped off and because it's something else semi oil-related that is easy to check and doesn't require any major disassembly.

It very well could be your oil is too thick for current temps. In St. Louis at 15F, My oil hits right about 70-80 or more at high idle/warmup, and goes down to 15-20 or so at idle when everything is warm and flowing. Not even gonna touch oil choice again lol What does it settle out at when everything is warm? Could be normal(?)

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DriftDamage

Like I stated before it would never go past 90psi even in the coldest of temperatures here. Two weeks ago we got a major cold front and that was the coldest it got here reaching 20 F but even then it didn't go past around 90-100 cold start and then going down to around 40-60 when the oil was about 200F. This is the reason for my post because now it sits around 120+ cold start and around 90 when the oil warms up.

As for the second part I put in bold from your statement, YES I do beat the hell out of the car in the heat for extended times. My car sees a lot of track time.

Please refer to this video of me running a few practice drift laps around a local track and noticing how after only 2 laps my oil temperature gauge's alarm will go off...

https://www.youtube.com/watch?v=aBIpOH6VJ0s

Z28ricer

Hooking up the gauge sending unit to a T and pressure checking should be your first step, there aren't many ways around this, certainly nothing that's simpler and easier unless you've got another gauge and sending unit of the same type to test with.

You'd need to know what the output range of the sending unit is to test further with some additional electronics, but right now square one for you should be simply using the air pressure check to see whether the gauge is working properly or not, prosport isn't exactly the best when it comes to gauges, and changing other things could be wasted time/money if you're using a bad gauge for reference.

Only other option I can suggest is a cheap mechanical pressure gauge, remove the sending unit and connect a mech gauge, then check pressure again.

DriftDamage

I'll check that valve too and the lines from the 'tee' as you say.

When the oil warms up to about 200F the pressure sits around 90psi. If it went down to the normal 40-60 which i'm used to I wouldn't be worried about this

Z28ricer

Don't even bother, he doesn't have a clue how it works, neither have any chance at remotely doing this to your oil pressure.

DriftDamage

In that case I'm going to ask some friends if they have mechanical gauge laying around to double check my pressure. I would hope it's a faulty sensor.

I guess the real question is how damaging can this be if it is not resolved soon?

Mikester

ANYWAY... Easiest way to verify is to direct-connect a mechanical gauge to the sender to verify like Mr. Congeniality said above.

However, since I am an idiot with no clue:

If it's a bad gauge or sending unit, no big deal & good for you; but you'd probably want to replace sooner than later. If the oil pressure IS as high as your current gauge reads, you should probably start working to diagnose/fix it as soon as humanly possible as it could end up being a showstopper.

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Z28ricer

It really depends on whats causing it and where the increased pressure is, in relation to where the gauge sender is, your turbo could be seeing the full pressure and possibly be damaged, or if there is something stopping a passage between the sending unit and the turbo, or bearings you may damage components downstream of the sending unit.

Honestly I wouldn't do a bit of speculating, or worrying, or driving, until another pressure gauge has been installed to determine whether there is an actual oil pressure issue, or just a gauge issue.

Z28ricer

Oh goodness, now i'm unhappy, because some fool on the interwebs doesn't have a clue about engine oil, runs around making suggestions and comments based on his own lack of knowledge, and then denies everything based on his own lack of credentials

Kingtal0n

1. Do we all agree, the reason they started the multiple viscosity (5W-30) instead of just a straight number (30W) was because of the need for thinner oil during startup and thicker oil when temperatures rise.

2. Do we all agree, that the majority of manufacturers use multiple viscosity oil from the factory (5W-30).


I do not agree with the first statement. We cannot simply look at this as thicker, thinner situation. The oil with 5W-30 rating is not just "thicker" once it gets warmer, it is actually "no thinner than a straight 30W would be at XXXtemperature". Which could still be thinner than a 5W oil at colder temperatures.

So instead, lets ask, why do we want a thin oil during startup? Is it, perhaps, to quickly lubricate the engine's bearings and internal features?
Then it would seem that the lightest thinnest oil possible, would be an ideal startup characteristic.

So why dont they make a 0W-50 ?
The properties that allow oil to change viscosity subtract from its lubricative quality. The more of a spread between numbers, the less lubricative the oil becomes. Running a straight weight oil (30W) will have more lubrication property than a multiple viscosity oil. Have you ever seen "straight 50W racing oil" ? Why is that a "racing oil"?

Let us examine a racing engine characteristic. Loose bearing clearance when compared with factory engine bearings means that thicker oil is required. Stronger, dedicated, hardy oil pump hardware means the risk of failure due to excessive wear and tear related to pumping thicker oil is reduced.

Those two reasons are why I will not put a 50W in an OEM bearing clearance SR20DET. The factory oil pump does not seem to tolerate well the additional load of thicker oil, pumping into tiny bearing clearances, and the reduced effectiveness of cold-start lubrication is not acceptable. Remember that oil is pumping OUT of the journals while the engine is running, as much if not more than it is pumping UP into the engine. You cannot simply imagine what happens when the oil becomes "thicker".

Lastly, I want to point out, that a 50W oil at around 220*F~ there is no issue, and this situation is recommended for cars that live on a track.
In a daily driver, when the engine is mostly warming up for most of your drive (Q: how long does it take your daily to hit 220*F oil temp) It is DURING this time that the excessive wear and tear, unnecessarily thick oil takes it's toll.

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jr_ss

My first guess is the pressure relief valve sticking. Oil pressure doesn't just go up because of a cold front... Once warm it should drop back to "normal pressures". However, I do not know what the factory SR pressure relief valve is suppose to pop off at, so that doesn't help much other than pointing you in a direction.

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Z28ricer

All that rambling is cute and all, but again, you're trying to argue with the factory recommendation based on your extensive testing on what the oil pump can handle I guess ? For some odd reason, I think Nissan might have had good reason, beyond your speculation and spitballing, that the engine would be fine with up to 20w-50 oil in appropriate temperatures.