Thanks rbort and everyone else!

The thing is that when I bought this car the pressure was seriously messed up, it wouldnīt go over 2 whatsoever with a warm engine, idling at levels I wonīt say out loud...

So I bought it knowing there might be something funny with it, and had repairs in mind on the whole deal. So I immediately changed the oil and filter and it went ok at once, or at least as ok as it is now. And itīs gone about 6k km (4k miles?) in a couple of months, being stable.

Anything to check before changing the oil pump, as this is an expensive thing to change from what Iīve heard.

Again, thanks everyone! This forum is great for computer heads like me who love driving these cars, but have limited car mechanic skills.