Distributor

Good evening, friends, I'm Marco from Italy. A strange thing is happening to me. After installing the distributor cap according to the markings, after a short drive the car runs erratically. So, I open the distributor cap, place piston 1 at the top point, and see that the rotor is 180 degrees out of phase with respect to the marking on the distributor. What could have happened?Many thanks.

Hi Marco,
the crankshaft turns 2 times while the distributor turns once...
Just let the crankshaft make one more turn...

Are you sure you did not interchange the plugs in the cap?
Which make is the new cap? There are quality-problems...

Regards
Norbert

Good morning, Norbert, sorry, but unfortunately I expressed myself poorly.I removed and reinserted the entire distributor, matching the crankshaft pulley references with the mark on the distributor. I started the engine, but after a short while, the engine was erratic. So I checked and saw that the rotor was 180 degrees out of phase. How is this possible?All the components are Bosch factory parts, and the spark plug wires are correct for the ignition.
sono triste. 

Sorry, I forgot to point out that not only is the rotor out of phase but also the distributor shaft

They are not out of phase. Just turn the crankshaft by another 360 degrees and you will see this.

Regards
Norbert

OK, I'll try.
Thanks a lot, Norbert.
Have a nice day.