My EOP is at almost 5 bar at 65mph. At idle it drops to about 2.5. I know that at 5000 rpm it should be 3.5 bar. Any ideas as to the problem at highway speeds? Am I hurting the motor by driving the car. Thanks.

 

I never heard the 5000 rpm 3.5 bar statistic. Both of my cars show oil pressure at or near 5 bar at well under 5000 rpm. I tend to be more concious of the low end at idle. I can not imagine how high oil pressure could "hurt" under any "normal" scenario...........

 

Well you would not want it to high, but a reading of 5 at anything off idle (especially under load) I have always considered normal. I would be concerned if the oil pressure dropped down as the engine approached red line. Are you (or anybody else) showing 3.5bar at 5000rpm's?

 

It's the number quoted in the owner's manual. My guess is it's a low range number to account for higher mileage cars close to an oil change with 15000 mile old oil in the sump, for example. As you say, typically the pressure @ 5000 rpm is higher than 3.5 bar.

 

Mine reads the same as yours, but drops down to around 2.5 at idle, also. I've been told that this is normal and not to worry.

 

Wet sump engines can blow head gaskets with very high oil pressure. Dry sump (Pcars) need the high pressure to maintain oil supply to more oil points. If your running 3.5 bars at 5000 rpm, take it in to the dealer.

 

I checked this morning, I am at 3.5 bars at 2500 rpm, in the C4.

Also for reference I am running 5w 30 mobil1 and the car has 42,000 miles on it. there is approximately 4,000 miles on the oil and it was at operating temp when I checked it.

 

Gretch- interesting, I now wonder if my running 10w60 oil is having any affect on oil pressure. My car has 31,000 miles on it.

 

no sal, id say you got a clogged pump screen or your pump is failing or even worse, definatly take it in asap

 

Salazar,
I use 15 w 50 in my 928. the car has 96k miles on it. the oli has about 100 miles on it (just changed) and the EOP readings are the same for both cars at various rpm readings.

10w 60 does not seem to be on the list of approved viscosities. Why did you choose it?

Nivek, wouldnt your diagnosis result in LOW oil pressure readings, as opposed to high?

 

i thought he said it was at 3.5 at 5k rpms? thats prettty scary low

 

guess my new glasses suck

 

Why should he do that? So that the dealer can read the 996 owners manual to him? 3.5 bar is what the manual says is "normal" @5000.

 

3.5 bar is regarded as the minimum oil pressure @5000min-1 for the engine to operate safely. If I had an engine with less than 60,000 mls on the clock, I would expect over 4 bar under normal circumstances.

Cheers
Uwe

 

Uwe,

I'd agree that 3.5 bar is at the lower range of acceptable pressure....mine typically is above 4 bar at higher rpm, as you say. But the post I was responding to suggested (I thought) that 3.5 bar was too high. Maybe this thread is just too confusing..... .

Regards,