PV

Like to know if there is anybody out there who knows what the oil pressure in the new 997 or 997 S should be.

The manual is stating that it should be 3.5 bar at around 5000 rpm.

I assume that the pressure gauge should make some sort of sense. As far as I have seen the actual oil pressure is higher than the statement. I haven't seen any data yet, which talks about the initial oil pressure and where it should stabilize, after inital break in period and when running at design temperature.

PV

1999Porsche911

Same as the 996. Above 4.5 at 3,ooo rpm or more and 1.5 - 2 at a warm idle.

PV

So, it is not an issue that the oil pressure is significant higher than stated in the manual?

What is better, higher or lower, or is there no better in this area?

I was just wondering whether the bearings have to suffer more.

PV

1999Porsche911

Porsche has never gotten the pressure right in their manuals. Higher is better. With a properly filled oil system, when the car starts from cold, the pressure will jump immediately to 5 and then slowly come down to as low as 1.5 - 2 when the car is at full operating temperature. After this point the pressure will increase as RPM's increase. RPM's above 3,000 will show a pressure of 4.5 or higher. This is even true in hot weather. If your pressure is lower than that, you are probably low on oil.

PV

Thanks for the explanation.

Mine is indeed starting @ 5+ bar, and when warm idling it is sitting between 2.5 and 3.5 bar. I was wondering why the gauge is not showing up to 6 or 7 bar, as those pressures seem to be normal at high rpm's.

PV

A few weeks and 2700 miles later (yes, we are getting close), the motor is idling warm around 2.8 bar, and that is alreay so for at least 500 miles. Seems to be a sort of settling point for now.

1999Porsche911

I would check you oil level. That seems awful high for a warm idle oil pressure depending on the oil you are using.

PV

Oil level is perfect. Using Mobil 1.

The pressure is 2.3 bar by the way. I misread the gauge last time or the motor was not perfectly warmed up yet. This time it was and I let it idle for a few minutes.

1999Porsche911

Ok. Since youroil is the correct level, remember the readings of the oil pressure at various rpm's on your completely warmed upi engine. This will be your NORMAL readings. Changes from the NORMAL may indicate oil level changes or other problems.

Ihave never seen a Porsche read such a high pressure when the engine is at running temp. But, each gauge is diiferent an yours may be off a little. It boils down to what is the normal reading for YOUR car and not whether the gauge is reading high or low.

PV

I will watch the pressure and come back on it after few more miles.

Do I remember correct that somebody said a few weeks ago that it was better if it is higher?
Lets be more specific:

Idle: low oil pressure in the range between 1 and say 2.5 bar is OK.

At rpm: 4 or 5 bar is OK

The book states that it should be around 3.5 bar at 5000 rpm.

I originally asked the question as I thought that the higher pressure was going to create more oil leak, but a too low pressure at idle is indicating either to low oil level orleaking oil through the bearings and so on.

1999Porsche911

Oil pressure of 1 bar would be very worrysome. I never see below 1.5 bar. The needle will always be buried when rpm's are at 5,000.

PV

So we are talking bar absolute (bara). OK, anything below 1.5 bara is not good, I can agree with that if it is bara, as basically there is no pressure at all below 1.5 bara.

PV

I have to correct myself here. I assumed that the dial showed bara, but it is barg, as it starts at an ambient pressure of 0 bar, which is 1 bara.

Somebody told me that the "older" Porsches were running fine at 1 barg.

I'm still at 2.3 barg at 205 F.

Porsche991Leb

Hello All ,

I have the 991 , weather was around 35 deg C / 95 deg F , the car was like over 1 hour of traffic then went up the mountains with full throttle almost .. I realized that @ high revs at any gear the Oil pressure bar level is reaching the red line ( which is 4.x bar ) is this normal ??

Can anyone share his inputs ?

My car is 2012 Carrera S 991 3.8 L
Regards,

Mumbles

This thread is 9 yrs old..........