bleunetizen, i assume you have a 2011 or later model since you have the stock oil 'cooler'.
Not that i dont believe you but I find it hard to figure how you are overheating your oil at 23*c ambient. Even at 35*c or warmer, my oil doesn't go over 100*c and that's with just the stock cooler in heavy traffic so hardly any airflow in the engine bay. Even on a spirited drive on a warmish day i never encountered limp mode. i even simulated 108*c oil temp using a fixed resistor and there was no significant loss of power. Are you talking about full on limp mode or just a throttle lag?
But then in your later post you say the oil struggles to reach 80+? Over cooling the oil can be detrimental too!