The EPA hasn't yet released its final ruling on a proposal to freeze fuel economy standards. However, a different federal agency—NHTSA—has finalized a rule to freeze fines on automakers who exceed the standards.

The fines have been set at $5.50 per 0.1 mpg, per car the automakers produce that doesn't meet the standards, since 1997. These fines have amounted to tens of millions of dollars a year for automakers. For automakers with budgets approaching $100 billion a year, however, they amount to small change.

Some companies have opted to simply pay the fines instead of improving the fuel economy of their cars.

In 2015, in response to a Congressional mandate to raise fines for non-compliance across the government, NHTSA proposed to raise the fine to $14 per car per 0.1 mpg. Auto industry lobbyists complained that the proposal would cost automakers $1 billion annually, but when environmental groups along with New York, California, and several other states sued NHTSA, the U.S. 2nd Circuit Court of Appeals ruled that the increase could go forward.

On Friday, the agency released a statement saying the new rule freezing fines at $5.50 faithfully follows Congress's intent in setting the penalty rate at the highest reasonable amount according to the statute.

Even if the fines were raised, it may have been a moot point with the EPA (in conjunction with NHTSA) planning to freeze fuel economy requirements at 2020 levels through 2026. EPA administrator Andrew Wheeler has said he expects to finalize that proposal by late this summer, though automakers and 23 states have now stated their opposition to it.