Hello people – the following symptom: engine goes after a long drive( already after 10 km) to over 90° (also during the ride) and at a short standstill immediately to 100°. If it is cold outside, it remains clean on its 90° . On this problem I changed the following in turn: 1. thermostat 2. new water cooler ………………………………….problem was still there 3. climate cooler well washed out from behind……problem was always there after 4. new water pump ………………..problem was still there 5. new thermostat ( – also a new can be defective)- cooling system cleaner driven through the system)…… 6. voltage constant in the tacho changed ( now at least the display is constant) Meanwhile I am with my Latin at the end – can someone help me further ? Is there besides the one venting screw on the way to the heating cooler still a second one I would have forgotten?