Metro Rail Car 126 returned to Buffalo on Monday, and officials of the Niagara Frontier Transportation Authority greeted it like an old friend.

Not that they harbor any particular affection for a rebuilt subway car, but Car 126 has been absent from Buffalo’s rails since way back in 2004. That’s when it departed for Wilmington, Del., and the initial stage of a problem-plagued rehabilitation program deemed key to Metro Rail’s future.

So after nine years and four different production facilities, the return of Car 126 is finally providing hope to NFTA officials that years of delay and controversy over its more-than-$40-million “mid-life rebuild” program may be finally over.

“It shows we’re back on track,” NFTA Executive Director Kimberley A. Minkel said Monday, adding that she expects a “continuous flow” of rebuilt cars to the Buffalo subway through the end of 2015.

The third Metro Rail car to come back to Buffalo follows a string of bankruptcy and production problems that delayed the program for more than three years.

Indeed, after Car 126 traveled to the Delaware Car Co. shops in 2004 to be diagnosed for a design plan, it then wandered to Glenville in Schenectady County to the Super Steel locomotive assembly shops, where the rehabilitation program was originally scheduled.

But that company declared bankruptcy, and work then shifted to Gray Manufacturing Inc. in Hornell. After production disagreements there, the car later moved again to Italian rail equipment giant AnsaldoBreda at the former Foster-Wheeler plant in Dansville.

The NFTA aims to extend the life of the fleet that Tokyu Car Co. built in Japan in the early 1980s rather than purchase more expensive new cars. But the rehab program involving 27 cars fell six months behind in 2011.

After The Buffalo News again highlighted the problems in March, the NFTA summoned AnsaldoBreda to Buffalo to find ways to speed up production. The result was a new plan that accelerated the program by eight months, with the return of Car 126 providing the first tangible sign that the plan is finally on schedule. Authority officials now expect a regular return flow of Metro Rail cars to Buffalo after disassembly at the subcontracting Gray Manufacturing shop in Hornell and rebuilding at AnsaldoBreda in Dansville.

Hornell Mayor Shawn D. Hogan sharply criticized how AnsaldoBreda and the NFTA administered the program, pointing to the resulting loss of jobs at Gray Manufacturing. In fact, he predicted in 2011 that switching much of the production to Dansville would significantly delay the program – and it did.

He even suggested that the NFTA call in a $24 million performance bond posted by AnsaldoBreda.

But the NFTA said new pressure on the company resulted in expedited production methods that have now resulted in the first delivery from the batch of cars delayed in Dansville.

Cars 114 and 123 were returned to service in 2012. They mostly operate during nonpeak hours because of their inability to couple with older cars that have not yet been rebuilt and typically operate in a three-car train during peak hours.

NFTA spokesman C. Douglas Hartmayer said Car 126 now faces 600 hours of night testing before it can be returned to revenue service and work with the two other rebuilt cars during peak hours.

The car is expected to return to duty in a few weeks.