Can I get a bus tour at Pudong airport after 11 am and return to that airport by 9 pm, Sundays?

To be honest, the time is tight.
You can take the maglev train at the airport, get to Longyang Road Station. Then transfer to subway line 2 to West Nanjing Road. It takes around 30 minutes on the way.
After arriving, walk to No.68 West Nanjing Road and you can find the sightseeing buses are located at the opposite of New World Shopping Mall.
You need to return back to the airport earlier in order to avoid traffic jam on Sundays.