How do I open Data Pump Import Wizard in SQL Developer 4.1?
View > DBA



Add a Connection

Expand the tree.

Go to the Data Pump node.

Expand, expand again to get to existing DP Import Jobs.

This will show the results of 

SELECT
    name,
    fname,
    type
FROM
    (
        SELECT
            job_name name,
            owner_name
            || '.'
            || job_name fname,
            'DATAPUMP_IMPORT_JOBS' type
        FROM
            dba_datapump_jobs
        WHERE
            TRIM(operation) = 'IMPORT'
    )


To create a new one, right-click and use the Wizard.