Oil is 0w40

 

Maybe 4 bar is normal start up pressure for a 0w oil...I e never used anything below a 5w in either of my 997.1s.

I'd say the 0w is thin for cold start and it's probably Mobil 1 if a 0w40 which means the visxity is shearing and why you also have low oil pressure when hot.

M1 just isn't a very good oil for these engines and also usually shows higher copper and iron bearing wear than others do too.

 

See all these points are valid. However it doesn’t explain the gradual decline in oil pressure. If the above was the case then after changing the oil, atleast the pressure should have gone back up to above 1 as it used to be before. The fact that it is in the exact same position makes it seem as though the oil itself is not the cause. Plus I live in the Middle East, hence why the 0w.

 

You don't need a 0w oil unless your temps are close to 0 degrees. 5w40 works just fine for cold starts at 15-20 F. I don't think you have a problem other than the oil you're using. Try something else and see if it does the same thing. If you can't get Driven where you are, try Motul 8100 xcess 5w40 or the Liqui Moly in the green jug, whatever that is - the others don't work as well unless you add MoS2 or Ceratec to them.

 

Bro the thing is, it has gradually gotten lower over the past few months. Oil viscosity doesn’t explain this finding.

 

Yes, that may be the case. If the oil dilution by fuel is high, the viscosity and the oil pressure will of course change. How high was the fuel content in the oil, the analysis should show that.

 

Haven’t checked that tbh. What are some reasons this can happen? I.e. the oil dilution.
However wouldn’t that issue be resolved once fresh oil is put in?

 

Post the oil analysis report.

 

I’m afraid it wasn’t as much a report. It was tested with magnets. Showed nothing.

 

These engines are almost all aluminum, so a magnet is only useful to show you ferrous debris from either the IMS ball bearings or main engine bearings if you've worn down through the prior layers.

You should really have a real used oil analysis done so we can see what's worn out in the motor contributing to the low oil pressure.

 

Ah well guess I gotta wait till next oil change. Anything I can do meanwhile? I saw the oil and while I can understand that seeing is not enough, it was very clean.

 

You can't really tell anything by looking at oil unless the engine has major issues and then in the sun you can see the reflective metal particles reflecting the light. You need to send a sample off to a company like Blackstone or Speed Diagnostics to do a thorough quantitative analysis. We're talking about parts per million when it comes to metal wear so you're not going to "see" it when looking at the oil.

Only thing that will increase the pressure in the interim is to go with a higher viscosity oil, but that's not going to tell you what's wrong and why the oil pressure is low and falling.

 

Yes, I’m using 5 W 50 on my 997 GT3. The car seems to like it and the oil pressure is higher. My previous 5 W 40 Motul, Mobil one and Liquid Molly were showing a lower than average viscosity during Blackstone oil testing.

 

So two things. First, this is the oil level reading after adding 7 L of oil

Secondly, doing some research, what about the pressure relief valve? Supposedly that is something that can cause this low pressure. Could explain the relatively low oil pressure at start and at idle. Also goes with the picture of gradual decline of oil pressure over months.
Plus how does one check for the oil pump integrity? Can it cause the symptoms the car is experiencing?

 

It could actually be a defective pressure relief valve in the filter housing, but I doubt it. So replace the filter and housing at the next oil change. To be on the safe side, I would do this immediately and then add 400ml. Edit: The only issue with a defective valve is partly unfiltered oil, not a problem with the pressure itself.

On page 78 of my manual it says that the oil pressure should be at least 3.5 bar with warm oil (80°C+) and 5,000 rpm (997 Mk1).