Auto_Werks 3.6

I just got back from a 20 day business trip and went celebrate my return with my turbo, but it confronted me with a new problem…

Symptoms:
On cold start the oil pressure will only go up to 3 Bar. (my car always sits at 4.5 or 5 bars cold).
As you rev the engine the oil pressure will climb slightly, but it maxes out at about 3.3 bars… not good!
At hot idle the oil pressure will drop slightly to ~2.8 bar.

What I have done:
Checked the oil, no problems there.
Changed the oil pressure sender out with one from a parts car and got exactly the same readings.
Shorted the wires to the gauge, and was able to get a reading of 5 bars.

What I plan to do:
Check the torque of the crankshaft pulley.
Change the oil filter (long shot)
Check the oil pressure relief valve (last resort).

Does anyone have any other ideas of things to check, or any advice on removing the oil pressure regulator with the engine in the car?

87944turbo

Looks like you have a good list going.

If your talking about the OPRV, should be no problem to remove it.

2bridges

X2 have a good plan. would be my aproach as well.

Only change is before I tore into ORPV - would try another guage, even aftermarket mechanical to get a second verification on actual oil pressure reading

caster951

What kind of oil are you running Ryan? With the heat today here maybe that is it if you are not running 20w50?

What are you doing working 20 days in a row? Geez,
Shane

kasturbo

OPRV can be replaced with the motor in and even the headers on. It's tight, but can be done.

Auto_Werks 3.6

The oil that's in it is Redline 20w50...and I had it in a relatively cool garage. I usually have to run the car quite a while before I see that stuff thin out.
As far as work goes... I'm taking this friday, saturday, sunday off... but that doesn't quite seem like a good ratio. All I can say is, at least I'm paid by the hour~!

bearone

hot idle/2.8 isn't bad

87951

Auto_Werks 3.6

well.. The crank pulley was NOT loose.

I looked into the sensor a little more today seeing as I installed a used replacement with an unknown history. I noticed that I can remove one of the wires (the sliding spade connector), and the reading stays the same. That doesn't seem right to me.

Kevin or Shane, do you guys have a pressure sender that you know is good?

bearone

the same symptons with a replacement unit, you might have a wiring problem from the sending unit to the gage/harness or the gage itself.

87951

Auto_Werks 3.6

This post is for the archives...

I finally figured out what my low oil pressure problem was... After some more research and testing, I swapped my oil pressure relief valve out with a known good unit and all my problems are gone. After taking my OPRV apart, I'm not entirely sure what was causing the problem, because everything looked in reasonable shape. There was some slight scoring on the piston, which is what I assume caused the trouble, but it was not significant damage...

caster951

Ryan,
I dropped the oprv off with Kevin yesterday, so he has it! Hope that helps.
Shane

Auto_Werks 3.6

Shane, I got his message but I didnt have a chance to call him back. I hope to be able to pick it up on Friday! In the mean time, I still have Artie's valve...so needless to say I've been driving.
Thanks!

schadenfreude

So what sort of oil pressure do you get now, out of curiosity? Mine is 5+ bar cold, and 2 bar hot (0.5 - 1 bar VERY hot!). Should I be concerned?

billindenver

Change to synthetic and you shouldn't get down to .5 and 1 bar when very hot anymore.

toddk911

So this means the valve was not allowing more oil pressure or just giving a false low reading?