quick oil pressure question

[Zoig]

The interior gauge is just there to show that oil pressure exists. As long as the result is verified i would not count the accuracy. out of the small I5 sample size i have measured it reads too low around 0.5Bar (your milage will vary).

[varia]

According to which Audi technical service bulletin? Too low IMO.

According to Marc S.
Good enough?

http://theprojectpad.com/viewtopic.php?f=10&t=1833&p=72844&hilit=bar#p72844

[Error404]

I am sure 1 bar at idle is fine. The low pressure warning is triggered at just 0.3bar.
The factory manual specifies a minimum of 2.0bar at 2k rpm and 80c.
Interestingly it also states that maximum pressure should not greatly exceed 4.5bar or the hydro tappets pump up and loose compression.

[Error404]

Pressure is relative to flow x resistance. So larger oil clearances or wear will reduce resistance, requiring more flow to maintain pressure. This is only really noticed at idle as the pump is is displacing a fixed amount of oil. Increase the pump speed (more rpm) = more flow, resistance is the same so pressure increases.
Resistance is relative to viscosity so you can run an oil that is more viscous at temperature to increase resistance and therefore pressure at idle. Clearly once the relief valve opens it makes no difference, so the more viscous oil only helps increase pressure at low rpm, assuming the relief valve and oil system is working correctly.

[terrybullwon]

A lot of sense right there

[Bowie69]

Also agree 1BAR at idle when HOT is fine, mine has always been around this, for almost 100,000 miles now.

Seems like you have a mechanical problem, or fingers crossed a weak pressure relief valve spring.