MU 2176 then EU 6678 at Pudong
Xi'an → Shanghai → Chengdu
Timetable, Shanghai time
15:45MU 2176 from Xi'an at the gate
12:55EU 6678 to Chengdu leaves the gate
21 h 10 apart on the timetable, overnight
EU 6678 leaves 21 h 10 after MU 2176 arrives on the timetable: more than half a day, so not a connection we count.