My oil pressure is normal when the engine revs, but at idle it drops to 0 or almost. It's about 5-10C outside, so I recently switched to 10W-30 at my last oil change. I did the exact same last year and altough the idle oil pressure would drop a bit with the thinner oil, it would always stay above 1 bar. Engine is not louder than usual or ticking or anything.

I guess it's either:
A-Bad oil gauge sender
B-Bad oil pump
C-Bad engine
D-...you tell me!

B is highly unlikely, C could be a possibility but I doubt it... I think I have and external oil gauge somwhere, but where do I hook it up? And where is the sensor located? I don't recall seeing it when I changed the head gasket a month ago.

Here's a video of it in action:
https://youtu.be/TU6C4bGhA70

I think it could be improved ,but as long as you have good oil pressure at high revs its the main thing . As the oil is there anyway and wont go any other place than the engine . Me i would try a new oil pressure sender for a quick fix .If still the same ,replace oil pump ...Main check is when engine is hot aftet a run ,then check pressure after tick over .For you own peace of mind you could fit another oil pressure guage . That will put your mind at rest .. I have the 2.6 and use semi synthetic Castrol 10w 40 oil

My 190E 2.6 did that. It was the sender.

It is the sender.

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'84 190D 2.2 5MT (Red/Palomino) Current car. Love it!
'85 190D 2.2 Auto *Cali* (Blue/Blue) *sold*
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