Low oil pressure?? + crankcase pressure?
06-28-2005, 07:57 AM
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Low oil pressure?? + crankcase pressure?
well, my 968 is 100.000 miles and i was seeing low oil pressure at idle when hot, around 1.5 (4 bar cold) although the the plugs seem very clean with no blowby, nice colour, i thought that the oil was too thin for the engine, since the top end rattled a bit when cold, and based on the oil pressure i changed the oil to MObil 1 15w-50, hoping that it would smooth the engine and also quiet it down.
But the truth is that the oil pressure does rise more sharply during normal driving, and at cold it 4.5, although at normal temp, its a good 2 bar solid, except sometimes the engine stumbles a bit at idle and the oil pressure variates as well, but sets down at 1.5 bar again and stays there, which i think ist a bit low for this oil..?
at the same time i found that by removing the oil filling cap, theres alot of cranckcase pressure around, and i found that the tube feeding into the throttle body its very clean like the car has no pressure at all, is it possible that cloged up?? the breathing pipe??
But the truth is that the oil pressure does rise more sharply during normal driving, and at cold it 4.5, although at normal temp, its a good 2 bar solid, except sometimes the engine stumbles a bit at idle and the oil pressure variates as well, but sets down at 1.5 bar again and stays there, which i think ist a bit low for this oil..?
at the same time i found that by removing the oil filling cap, theres alot of cranckcase pressure around, and i found that the tube feeding into the throttle body its very clean like the car has no pressure at all, is it possible that cloged up?? the breathing pipe??
07-03-2005, 01:47 AM
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I am seeing something similar in my '92 968 coupe. I just recently had a buddy change the oil while they were putting new shoes on the car. Well since then I have noticed that my oil pressure drops to 4 bars once the car is warm sometimes dropping to 1.5-2 bars when sitting still. The only two things that were changed are the oil filter and the oil. I thought maybe the oil was giving me this problem, but I changed it out with some good oil and the problem is still present.
I have only seen something similar one time. I had the belts replaced on my '85.5 944 N/A and when I picked the car up I noticed the oil pressure wasn't where it should have been. I took it back and come to find out they tightened one of the pully bolts too tight and that caused that to happen.
Don't know if that will help. I will post more if I find more.
Peace!
I have only seen something similar one time. I had the belts replaced on my '85.5 944 N/A and when I picked the car up I noticed the oil pressure wasn't where it should have been. I took it back and come to find out they tightened one of the pully bolts too tight and that caused that to happen.
Don't know if that will help. I will post more if I find more.
Peace!
12-15-2005, 01:12 AM
#4
Three Wheelin'
I believe that the factory manual states that oil pressure should be 1 bar or more at idle when warm. Mine is 5 bars at idle when cold and 2 bars at idle when warm with Mobil 1 15W50.
As long as your pressure is going up to 3 to 4 bars while revving the engine I think it is fine.
As long as your pressure is going up to 3 to 4 bars while revving the engine I think it is fine.
12-15-2005, 04:23 PM
#5
Rennlist Member
I think its cracked pickup tubes as well. Your symptoms are an exact of that condition. Were the balance shafts misaligned for a long period of time? If you hear the cam tensioner chain rattling in the head, its definitely oil pressure related and that is from the oil pickup tube sucking air at times instead of oil.
Raj
Raj
