Hi all! Meanwhile the problem with the oil pressure message was solved. At the first we tried with another oil cooler (Nissens was on the engine and replaced with a used oem) but no change on the pressure error or high oil temperatures. The service guy,after digging more inside the motor, found that the oil sump was clogged and because of that some finger follower set ( https://vehiclelifetimesolutions.schaeffler.com/en/catalog/auto-parts/engine/engine-timing/rocker-arm-finger-follower/accessory-kit-finger-follower/p-TA-3320-4230076100) was worn, so he replaced this set together with some seals and stuff around the upper part of the engine & injectors...but he said the main cause for the oil pressure error was the clogged oil sump.Tested the car few times on high way on hot whether and no error appeared but I observed that the oil temperature is rising to 130 Celsius on long highway trips at 130-140 km/h.The service guy said that this is normal...What do you think?