Motor does not start and too high idle speed

Hello, my 80s – type 89 – PM still makes me crazy. In the morning he doesn’t want to start, always takes a good 20 seconds to ignition until he finally arrives and takes a good half minute until he has reached his nearly 1000 revolutions in a stable way. If I just start it, it can come to Ruckler and sudden power loss, but after a few minutes it then runs perfectly. But then I switch off the engine, e.g. go shopping and then want to start again, he jumps immediately but the speed shoots up to 1800 high and stays there. Oftentimes the idle speed dances between 1800 and 2200. When the water temperature reaches approx. 90°, the speed drops back to approx. 1000 and the car behaves great. Unfortunately, I am with my Latin at the end and would ask for helpful tips, what I could test that can trigger these phenomena. Have already changed caps, fingers, ignition lines and candles – everything without improvement. Recently I replaced the petrol filter, which has brought an improvement. Before I could start the car again?