feelstranger

Here is the problem- 91 NF with 20W 50 oil. Engine oil pressure is fine at idle and driving for the first 10 + minutes or so. When oil temp reaches over the line between 60C and 130C the oil pressure *suddenly* begins to drop while driving, down to 2Bar at least - No I'm not cruising around like that!
The question I am trying to answer is what is the route of the oil in the system and could plugged lines to /from the oil cooler (not currently installed) cause this as the oil thermostat began to open? What is the path of oil in this system with the thermostat open versus closed?
Are there other things that could cause this?
Thanks for your help!
BTW, I'm going to install the cooler, but not If this engine has other major issues to deal with first!

MiB@100-2.3NF-91

My similar problem:

<a href="https://forums.audiworld.com/v8/msgs/65297.phtml">Part 1.</a>

<a href="https://forums.audiworld.com/v8/msgs/65674.phtml">Part 2, Update</a>

feelstranger

Thanks, but though similar, I don't think these are related issues.
I guess I'll need to add the cooler and see what happens.