Engine does not start

Hello, I have the following problem of the 1,9 74 KW engine does not start. After a longer start the engine starts slowly, but then runs normally and runs without any error. Also jumps immediately again. If I take the vehicle off again longer, it starts again from the front, only difficult to start. Leak oil test was carried out, since all four nozzles were the same in the volume output. Rail pressure I can not read out yet, since I have no tester. Can you check anything else without testing r? Diesel filter, incandescent pins are new.