oil pressure

[unforgiven]

hi guys im new on here so a big shout out to you all

my volvo is a 11/00 V70 xc 2.4 (200bhp) auto
i have a oil pressure warning that comes on approx 10 mins after start up.
if i turn the car off and then back on it goes away but will come back on again.
i have had the sump opened and cleaned
oil pick up etc and the rubber rings that are there replaced
then resaeled with volvo sump sealer
all parts used were from volvo
new oil and fitler also
new oil pressure swith
oil usesd is 10w-40 semi magnatec
after all this i still have the warning????
im very confused as to why
can anyone help as the garage cant seem to see any prob at all with the engine
please

[billr99]

Have you tapped a real pressure gauge onto the oil galley to see what your real pressure is at the point the message comes on? Seems to me that it doesn't make sense that you lose pressure after 10 minutes. Car should well be warmed up by then and any mechanical issues with relief valves or the pump should show before that. Possible software problem in the warning system maybe or some kind of wiring fault that shows itself only when it reaches a certain temperature?

Good luck,

Bill

[Chilled Man]

actually ... once your oil warms up it becomes thinner and that is the reason why you would see it .

If your oil pump seals are going out in the oill pan after the oil warms up it might start to leak past .

But ...... to throw that thinking out the window .

When you first start your car up your oil pressure is the highest around 100-120psi and then after the car warms up at full temp its about 20-30psi while sitting still .

While driving it ranges anywhere from 30-80psi .

[unforgiven]

how come if i turn the car off and then back on the oil message warning goes away?
is this and electrical problem on these cars?

[unforgiven]

is there no fix for the low oil pressure then?

[JRL]

actually ... once your oil warms up it becomes thinner and that is the reason why you would see it .

If your oil pump seals are going out in the oill pan after the oil warms up it might start to leak past .

But ...... to throw that thinking out the window .

When you first start your car up your oil pressure is the highest around 100-120psi and then after the car warms up at full temp its about 20-30psi while sitting still .

While driving it ranges anywhere from 30-80psi .
Not that much Justin.
No car has over 60-70 lbs cold pressure
Hot ranges are from (should be from) 30 to 45-50

[billr99]

is there no fix for the low oil pressure then?

Let me ask the question again. Are you sure you have low pressure? Have you put a real and accurate gauge on it to get the electronics out of the equation and see what the pump is really doing? Do that and perhaps some of us can make some additional suggestions.

Cheers,

Bill

[Aviator]

Here are the oil pressure specs as per Vadis.

Oil pressure minimum (at 100C)

800-850 RPM .10MPa = 14.5 PSI
4000 RPM .35MPa = 50.76 PSI
Maximum (relief valve opening) .48 MPa = 69.6 PSI.

100 to 120 PSI would cause seal damage and severe leakage, not to mention the possibility of catastrophic engine damage.

Dave.

[Chilled Man]

Not that much Justin.
No car has over 60-70 lbs cold pressure
Hot ranges are from (should be from) 30 to 45-50

thats not what my oil pressure gauge says every time I start up my wagon ...

[JRL]

Well then you have a BIG problem or a really screwed up gauge!!! :eek:
NO GASOLINE ENGINE runs with more than 60 or so pounds of oil pressure COLD and usually no more than 30-40 HOT.
Justin, if you were running 100lbs cold, it would puke out at every seal!

[martinperry]

Back to the original failure, as I have posted before, I had failing oil pressure, and on sump removal found the seals on the pipe that runs inside the sump from the filter to the cooler had been misassembled. Once replaced, all perfect.
That said, I would definitely put an external gauge on before dropping the sump again.
as for 120 PSI, don't be silly! I reckon the head would come off at that sort of pressure!!