Hello dear Porsche specialists. My new passion for her first suffering. No different to expect at a Porsche 928S year 1980. But that’s also why I bought it. ;o)Situation: 1000m after starting yesterday a pressure drop when accelerating uphill ended my sun trip. I still came home (mountain with stand gas), but now strange things happen when starting. After studying in this forum I quickly refilled 0W40 Mobil1 oil, since last week I had filled up n liters 15W40 (according to the manufacturer) to dilute the oil again. Beginner’s error…Analysis: Engine can be started without problems. Battery, rev indicator and tank indicator move rhytically up and down, the engine runs restlessly and goes out after a while. In the rear of the vehicle is a permanently audible noise of a small running engine (similar window cleaning nozzle motor). After that, the noise was gone. However, when the next start and drive of 5 meters is back again. Safe for the antenna removed, noise remains. Safes for windscreen wipers at the rear, removed, air filter cleaned at the front, noise remains. Safe for the fuel pump removed. Engine does not start. The more often you start the engine, the longer it stays on, but still does not run round. Cause of error: I hope one or the other has pity on me and can help me. fen. The weather is so nice and I would rather drive the car outside or repair it than look for the faults on the PC. Thank you very much, Heiko