Looks like this problem is hard to solve for me alone.
The car has gone 130 000km.

The car works fine, but the oil light comes on at idle.
When I increase rmp a little, then the light disappears.
The oil level is of course checked and the oil has specifications recommended for this car.

I have dismantled the sump and there doesn't seem to be problems with the strainer and the filter.
I also disassembled the oil pump, but it seems to be okay.

Now I don't know what to do next.

I am grateful for any suggestions that may be helpful in finding the solution!

 

a few possible causes 1) issues with the pressure sensor 2) the o-ring/seals in the pump are leaking pressure (sounds like you did the r+r here) 3) the oil pump components are worn and out of spec . It looks like you already cleaned the pick screen etc. As always, make sure you are using the factory recommended oil weight.

 

Thanks for your feedback mt6127.
How can I check if oil pump components are actually worn and out of spec?
Feels tight when I spin the parts, but I find it difficult to judge when I do not have a reference pump with new parts.

 

there are clearance values between the pump components that would probably be listed in a full shop manual or the VIDA/DICE software. But, if you are going to to to the trouble of pulling the pump back out to measure tolerances, you might as well simply install a new oil pump. I'd probably start by replacing the oil pressure sensor first, then consider a Seafoam treatment for the oil to see if that removes any gunk and helps restore pressure at idle. If that doesn't help then you probably should put in a new oil pump with new seals/o-rings etc. I am also assuming you followed standard procedures for priming the oil pump upon its reinstall as well.