Many riders approved when the MTA closed three subway stations on the R line in Brooklyn last year for renovations.

"It's about time. It's been many years without a damn elevator," one commuter said.

But not everyone is on-board with the improvements, which are now under way or planned on the N and W lines in Queens.

"Well, yeah, you would imagine some elevators would be nice, eh?" said another straphanger.

But on Wednesday, the MTA unexpectedly withdrew two more rounds of renovations from a board vote because of mounting questions about the so-called Enhanced Station Initiative.

Mayor Bill de Blasio's appointees to the MTA Board questioned how stations are being selected for the upgrades, and the wisdom of renovating stations without adding elevators to improve wheelchair access.

"Obviously, we're having a pretty intense debate about every penny," City Transportation Commissioner Polly Trottenberg said. "I think we all agree: Let's spend it in the way that gets the most bang for the buck."

The decision delays a vote on the renovation of eight stations in Manhattan and the Bronx, including along the Seventh and Eighth Avenue lines at Penn Station.

The Enhanced Station Initiative has been a pet project of Gov. Andrew Cuomo, who controls the MTA. Critics say it emphasizes cosmetic improvements over projects that could make service more reliable or improve accessibility.

Barely a quarter of the 472 stations are now accessible to people with disabilities.

"I've asked this over the past three months: How is accessibility and the station initiatives coordinated?" MTA Board Member Carl Weisbrod said. "I'm still waiting for an answer."

MTA Chairman Joe Lhota declined to say if accessibility upgrades might be included in future station renovations — although the agency does plan to spend $965 million to add elevators at 19 stations as part of its 2015 to 2019 Capital Program.

"The whole point of doing it on a pilot basis was to get it done right on these other ones and then scale it out," Lhota said.

The MTA Board is set to resume its discussion of the Enhanced Station Initiative at February's Board meeting. As for the stations in Astoria, the first two that closed in October are set to reopen this spring.