aryland's hotly debated auto emissions control program, which appeared headed for defeat in the General Assembly, was revived today in a compromise plan that would reduce the $9 inspection fee to $7.50.

Gov. Harry Hughes announced today his support for the compromise, which represents an attempt to make the controversial program more acceptable to voters while still meeting federal clean air standards by 1987, legislators said.

The new proposal, worked out with House leaders over the last two days, will cost the state about $1 million because of the lower fees, Hughes said. Under the original plan, the state would have netted more than $10 million in extra revenues.

The compromise plan, which will be introduced in the House this week, retains the requirement that motorists have their cars' exhaust systems inspected in 1983, but would not require repairs until 1984 for cars that fail the tests.

Many legislators have tried to kill the emissions program, insisting that the Reagan administration is likely to relax clean air regulations. They also say the program is likely to be unpopular with voters. The program requires all motorists in the Baltimore and Washington metropolitan areas to have their cars inspected annually starting Jan. 1, 1983.