Oil Pressure issues

[Thuppu]

Great that you get the issue sorted out. Also the oil pressure sender can wear out when it gets old, and can give you 0,5 bar too low readings.

[rs200]

yes.. yesterday I change them too , and it was the same .
for now I have to fix out gauge, there must be some cold join.. I know it is..

[A80Avant]

@ rs200

the rs2 auxiliary gauges come in a triple electronic plaque and not as 3 individual gauges. Which contacts did you clean to retest the gauge? I may have a similar issue, or at least need to check if i have as my mechanic used the break in oil which is a 15W40 mineral one and the warm idle was at 1.5bar, wheras with the 10W50 i was using it was 2.2 to 2.5 bar on the same gauge. Obviously with the thinner oil would expect a difference, but i want to make sure anyway

thanks
vas

[rs200]

well gauge for oil have 3 contact. 1. and 3. are on electric plate and 2. contact are on gauge. so I clean 1. and 3. contact with fine sand paper.
2. contact you can't clean because they are on bolt..

A80Avant.. you said that with 10w-50 you have 2.2 bar on hot idle? and 15w-50 are much better oil? which one did you use?

[A80Avant]

on the mineral that my mechanic just used for breaking in the engine, which is 15W40(not 15W50), the warm idle pressure was 1.5bar.

On the fuchs titan that i used normaly before the rebuild it was around 2-2.5bar depending on how hot the engine would get.

however i dont know which type of mineral oil he is using and obviously the fuchs titan being fully synthetic and a better oil, is also much thicker at 85C than the mineral one, which can explain some pressure difference.

I have bought to use as a fully synthetic after the breaking in of the engine the amsoil 10W40, and i just want to be sure that the gauge is reading true, so that the thickness of the oil is actually causing the difference in the pressure, and not something else! I could be having the same 0.5bar loss as mentioned above due to age of the gauge, as on cold start it showed 4.5bar on the mineral oil.

[rs200]

if your engine is fresh rebuilt with all new parts , than it's good to drive it first 1000km on 15w-40.
than after that, you put oil which you want.
before all this "oil pressure problem" I use 10w-40. I just want to test with 15w-40 , because I think that I will get same oil pressure like my friend have on s6 with fresh rebuilt engine.
so is your sugest to use 10-50?

[A80Avant]

if the amsoil i have (10W40) generates low pressure at warm idle, then i may go back to 10W50 or try 5W50 as the latter has specs somewhere in between the 10W50 and 10W40. The higher the warm grade, the thicker the oil, and therefore pressure should be higher, however i have been looking at oil specs and sometimes you can be amazed as one oil with 10W40 may be very close to another with 5W50 etc.

my whole point is to find the ideal oil to match audi's specs on what the pressure should be on cold and warm temps.

[rs200]

so the I want to have good pressure at idle and good oil.
I lot of oil , but newer 10-50. so you think that will be good?

with 10w-40 you will newer get good oil pressure at idle. I think it is like water. I want to find more compact oil for engine.
could 10-50 be it? we will try.

[A80Avant]

im hoping to use a 10W40 in winter here in the UK as the temps do not go that high. Also my car idles at about 85C coolant temperature anad a larger oil cooler as well. If it doesnt work, ill go to 10W50 or 5W50

[Tonks4x4]

Here is the list of recommended Valvoline products for RS2
SynPower XL-III 5W-30
SynPower MST 5W-30
SynPower MXL 5W-30
DuraBlend MXL 5W-40
DuraBlend 10W-40
MaxLife Synthetic 5W-40

And the 15W40 oil spec currently used for running in is

SAE Viscosity Grade 15W-40

Viscosity, mm2/s @ 100 ºC. ASTM D-445 14.8
Viscosity, mm2/s @ 40 ºC. ASTM D-445 110
Viscosity Index ASTM D-2270 138
Viscosity, mPa.s –20ºC. ASTM D-5293 <7000
TBN, mg KOH/g ASTM D-2896 8.5
Pour Point, ºC ASTM D-5950 -36
Specific Gravity @ 15.6°C. ASTM D-4052 0.879
Flash Point, COC, ºC. ASTM D-92 218

[A80Avant]

hmmm that is interesting, as the 10W50 fuchs has 116@40C and 18.17@100C

im wondering if the synthetic properties have much to do with it,as the specs are not too far off. Unless the 14 to 18 is indeed a huge difference

[rs200]

well today same problem.. 1 bar at hot idle.
at monday I will go and buy new oil pump . I'm prepare to change part by part until I fix this problem.
maybe I'm mad but I wont pressure like it was before when I rebuilt the engine.
I find one picture before 3 years when my car at hot idle have 2bar of pressure and it have 10w-40 oil inside.
and I ordered today 10w-50 (Midland) oil for it.. so we will see.

what is funktion of oil filter gracket ? they have one little piston inside and little spring.. you know that part on engine.
what did they do and when?
TNX
Igor

[Billman]

Did you changed the oil pressure sender? Did you checked the one way valve on the block? If you fitted arp main studs maybe you crashed it and you see different number than you should.

[rs200]

yes my friend I change 2 oil pressure sender. and 2 instrument closter.. everything is the same.
what is "wag valve" ?

NO I have stock main stubs .

[Error404]

I would check it with a proper gauge, the OE ones are not accurate.