The MTA’s inspector general is launching a wide-ranging investigation into the agency’s handling of its delay-plagued Second Avenue Subway project, officials said yesterday.

The probe will target the MTA’s repeated contract revisions, the amount of money it allocated to buy real estate to continue the project, and the reported trouble between the agency and Con Edison.

Manhattan Borough President Scott Stringer recently wrote to Inspector General Barry Kluger, asking that he look into those issues when trying to determine why the subway is substantially over budget and delayed.