Oil Pressure

[supra_rulz]

so i have two questions regarding oil pressure on a 1jz..
1. what is the oil's ave pressure when its warmed up?
2. is it normal for the pressure to drop when you floor it?

 

[IBoughtASupra]

It is not normal for the oil pressure to drop when you go full throttle. Did you ever change the oil pump?

 

[92TealSupra]

Normal when you put throttle on it no, cold start oil pressure is at around 41 I thought, I may be incorrect, but I know they have higher pressure then the 7M.

 

[supra_rulz]

ok....hmmmmm
I'm guessing that can't be good at all.
I have no idea if the oil pump has been replaced. I bought it with the engine already swapped.....
I guess more $$ for a diagnostics -__-

 

[IBoughtASupra]

Change the oil pump, most people just change the waterpump because of the hydrofan setup. A lot of MKIII owners would not even do that if the engine came with that same pump from the factory. That is why MKIV guys call MKIII owners cheap.

Not all of us are like that. I change everything in a swap. Take a look at my build thread for my 1JZ. It is simple,

1)Power
2)Cheap
3)Reliablity

Choose two and you don't get the third one. Change the pump and report back.

 

[mkiiichip]

The oil pan may have been changed with the swap, and there is a gasket and an o-ring for the oil pickup. Its more likely one of these have failed than the pump itself.
Either way, dont drive it until the issue is solved.

 

[Slow_Sc3]

Normal when you put throttle on it no, cold start oil pressure is at around 41 I thought, I may be incorrect, but I know they have higher pressure then the 7M.

the dude is asking about a 1jz you fool!!!!


you should have about 80-100psi of oil pressure at cold start and then around 30psi warmed up and crusing on the highway is around 50psi.

 

[Dylan JZ]

~70psi start-up

~40-50psi cruising

~20-25psi warm idle

 

[te72]

I guess everyone has different oil pressures, depends on oil type I would think. I run Rotella 5w-40 synthetic, and I'm ~60+ cold startup, ~40-55 cruising, and ~20-25 warm idle. Oil pump in my 1j has ~70k on it, might replace it when I pull the engine next summer.

To answer your question though, your oil pressure should rise along with rpm, not fall.

 

[Dylan JZ]

I'm running M1 10w-40HM ATM, but I'm going to switch to either Rotella 5w-40 or M1 5w-40TDT.. and yeah, I'd say there's definitely a variance based on quite a few factors, but our numbers are pretty close to what I consider normal (for that weight).

 

[IBoughtASupra]

Simply put, whatever oil you use, pressure should always increase when revving an engine, not decrease.

Change the oil pump, your bearings, crank, pistons, rods, camshafts, cam caps, head and turbo will be glad you did. You can check and make sure the strainer and tube gaskets are all in good shape or change them out since it only means dropping the lower rear pan.

 

[CyFi6]

Change the oil pump, most people just change the waterpump because of the hydrofan setup. A lot of MKIII owners would not even do that if the engine came with that same pump from the factory. That is why MKIV guys call MKIII owners cheap.

Not all of us are like that. I change everything in a swap. Take a look at my build thread for my 1JZ. It is simple,

1)Power
2)Cheap
3)Reliablity

Choose two and you don't get the third one. Change the pump and report back.

How exactly did you come to the conclusion that its the oil pump? OP's problem might not even really be a problem and for all we know he could be having electrical issues with the gauge. Changing the oil pump would probably be the last thing to do.

 

[IBoughtASupra]

I assumed that the original poster used a mechanical gauge or electronic gauge to get a solid reading. Changing the sensor to the 7M one would be good by using the DriftMotion oil line.

Both of those are good diagnostic methods. I have never seen a bad srock oil pressure gauge when hook up properly in the six Supras I have owned.

You can't expect me or anyone else to tell the original poster to do his own testing first before even opening this thread.

 

[CyFi6]

And I apologize if I came off as a douche that wasnt my intent, reading over my response it really sounds like it. But I think we should narrow down what the OP's problem really is before he replaces anything or it could end up being a costly repair in the end when it doesn't need to be.

 

[IBoughtASupra]

No offense was taken, don't worry about that.

The original poster has not responded in a while. He should first get a mechanical or electrical gauge and test the oil pressure that way. If he cannot do that, getting a know working cluster with an oil pressure gauge to swap in and see what it reads would also he a good option.

 

[te72]

Sometimes, despite the best intentions of building on a budget, and replacing potential issues on a system in order of expense and relevance... you still end up having to spend a good amount of coin on the expensive bits. Such was the story with my Mk2's cooling system. On the plus side, it was ALL new shortly after I got it.

 

[supra_rulz]

ok, so holly crap did you guys talk alot while i was gone. i'm sorry i havent been responding. i didnt get any e-mails so i didnt know people were trying to help out.

first things first. there is a electronic gauge for the water, oil temp, oil pressure. the water and oil temp seem to be working fine. all three of them drop a little when the turn signal is one due to power drain? but other than that they look to be working fine.
i just bought this car so i'm not familiar with alot of whats going on with this car.

unfortunantly i also can just go and test "variable x" because i dont have the tools or space. if its something "easy" i can research and try to do. but other than that i'm pretty much providing raw data.

now from what i read its either the oil pump or.....and thats pretty much all i understand by just looking over whats been said. if you guys have something i can do to narrow it down, besides spend tons of money to get something replaced before i'm sure thats it, please let me know and i'll try my best to do just that.

---------- Post added at 01:51 PM ---------- Previous post was at 01:48 PM ----------

and thanks everyone for helping out

 

[OneJArpus]

i see alot of oil pressure in my 1.5jz swap, 1jz head 2jzge block, all stock minus headgasket & HKS 264 cams. i see 80+psi cruise and the stock gauge it looks like its above 80 but below the 120 mark

 

[IBoughtASupra]

i see alot of oil pressure in my 1.5jz swap, 1jz head 2jzge block, all stock minus headgasket & HKS 264 cams. i see 80+psi cruise and the stock gauge it looks like its above 80 but below the 120 mark

Are you using the JZ pressure sensor or the DriftMotion line and 7M Pressure sensor to see the oil pressure on the stock gauge? I plan on hooking up a set of AEM gauges to monitor everything and just wanted to keep the stock oil pressure gauge as a back up.

 

[supra_rulz]

soooo, here's some "recorded" data that i observed

Water Temp: 180-190 F
Oil Temp: 190-210 F
Oil Pressure: "0"-6 psi
RPM: 400-500


Water Temp: 180-190 F
Oil Temp: 200-230 F
Oil Pressure: 35-60 psi
RPM: 1900-2100

normal?