A series of delays have kept a now fully completed subway station under Manhattan from opening

A long-awaited $2.4 billion New York City Subway extension is completed. In fact, it's been completed for months. But it hasn't opened yet.

The extension's opening was just pushed back again to late summer 2015, according to MTA board meeting notes obtained by transit advocacy blog Second Ave Sagas.

Vibrating vent fans, faulty alarm systems, and difficulty installing both the escalators and the custom-built inclined elevators have all contributed to the delay, according to the MTA.

Second Ave Sagas notes that MTA encountered these equipment difficulties due to contracts sold to the lowest bidder, made-in-America obligations, and "sheer stubbornness."

This is just one more snag in a long series of delays for the troubled extension, which will eventually extend the 7 train one station west to serve a new development over the West Side Yard train tracks (known as Hudson Yards) and finally provide a rail link to the Jacob Javits Convention Center.

The MTA's original date for completion of the project was estimated to be the end of 2013, according to the New York Daily News.

Although in August 2013 the MTA had announced the extension was "90% done," that date didn't happen. Former New York City Mayor Michael Bloomberg, who championed the project, did take a ceremonial first ride on the extension in December of that year before he left office.

By January 2014, president of the MTA Capital Construction Co., Michael Horodniceanu, said that because of complications with installing the incline elevator, the opening would be pushed back, The New York Times reported.

By June, additional complications with vibration from the ventilation fans prevented the opening. The public was promised a February 2015 completion date, which was then moved to sometime in April through July.

Now, nearly a year and a half later than the extension was promised to be open, the station has been delayed again - for the last time, we're hoping.

Well, we can dream.

In late March, the MTA released photos (PDF) of the nearly done station. Take a look below.