Where there’s smoke, there’s subway delays.

Subway service on Manhattan’s East Side went out of whack Friday morning after a train car started spewing smoke at East 86th Street.

Actress and one-time gubernatorial candidate Cynthia Nixon tweeted out video of passengers fleeing the sooty scene at 9:07 a.m., adding a dig at her former opponent, Gov. Andrew Cuomo, who trounced her in last September’s Democratic primary.

Most straphangers in the video covered their mouths to avoid inhaling the mysterious fumes.

“I’m ol gurl on the phone… just trynna make it to 5pm on this Friday,” Twitter user @YoungLootha wrote in response to Nixon’s original post.

FDNY responded to a call at 9:07 a.m., but the incident was over two minutes later, a spokesperson said. The MTA confirmed that a train with a mechanical problem had been taken out of service. No injuries were reported.

As a result of the incident, some 6 trains were running express and some 5 trains were diverted to the West Side 2 line, according to the agency’s Twitter account.