Gov. Cuomo thinks he can get cash for transit fixes via an old idea that would also curb city traffic: congestion pricing. The question is whether he’s willing to do everything that’s needed to make it work — and fairly.

The plan: Toll folks who drive into busy parts of Manhattan and use the revenue for transit. The fees likely would nudge commuters from their cars to subways and buses, cutting street congestion, while raising more transit bucks.

Just one problem: Cash for the tolls would come from average New Yorkers, who are already over-taxed and over-tolled.

The gov has yet to offer details, but his State of the State address reaffirmed his view that congestion pricing may be “an idea whose time has come.”

He cited “new technology” (i.e., cashless tolls) that offers “a variety of alternatives, defining an exclusive zone in Manhattan where additional charges could be paid.” And he wants the cash now: “Funding must be provided . . . this session, because the riders have suffered for too long,” he lectured. “We can’t leave our riders stranded anymore.”

Never mind that he’s been governor for seven years, so no one is more responsible than him when it comes to stranding riders.

But why squeeze New Yorkers for more cash? Yes, transit is vital, but the state has already slapped folks with payroll taxes, taxi surcharges and multiple biennial subway and bus fare hikes — to raise ever-more revenue for the never-satisfied system.

The MTA also needs to stop wasting billions. As The New York Times recently detailed , the cost of the East Side Access project (to bring the LIRR into Grand Central Terminal) stands at $3.5 billion per mile of new track, seven times the average cost of similar projects elsewhere.

Why? Because jobs here are overstaffed and workers overpaid. Companies and unions, facing little competition and lax oversight, conspire to jack up prices. No wonder there’s no money for repairs. No wonder the MTA forever thirsts for cash.

Those who’d be hit by new tolls are fighting back. “Enough is enough,” fumes one Queens commuter. “There’s no more money in our pockets.” With senators whose constituents would be hit opposed, State Senate Majority Leader John Flanagan says Cuomo’s Manhattan tolls just won’t fly.

Sadly, the only other idea on the table to address the MTA’s financial woes is even more of a non-starter: Mayor de Blasio’s “millionaires tax” is sheer lunacy, given the new federal limit on deductions for state and local taxes.

The gov might be able to lessen the congestion-pricing problem by offering offsets — say, lower tolls elsewhere. But, to be effective, the plan would also need de Blasio’s help in (for example) creating new bus lanes to make mass transit more workable.

If this is an idea whose “time has come,” Cuomo faces an uphill battle to prove it.