President Reagan's auto industry task force is scheduled to meet again today in search of a consensus on dealing with Japanese auto imports, with White House aides hoping to avoid a Cabinet-level showdown on the issue.

The auto industry policy issue is tentatively scheduled to come before Reagan and the Cabinet for decision on Thursday, officials said. First, a Cabinet-level task force headed by Trasportation Secretary Drew Lewis will try again to reconcile their deep differences over whether Reagan should formally ask Japan to reduce shipments of autos to this country.

Lewis, Labor Secretary Raymond Donovan and Commerce Secretary Malcolm Bridge maintain that a three-year voluntary import restraint agreement with Japan is essential to give U.S. automakers a breathing period to modernize and retool their plants.

Just as strenously, a second faction composed of budget director David A. Stockman, Treasury Secretary Donald Reagan and Murray Weidenbaum, chairman of the Council of Economic Advisers, have argued that import limits would aggravate inflation and send out a damaging signal that the Reagan administration isn't really serious about opposing government subsidies.

Treasury officials have been trying to assemble a tax relief package for the American auto companies that could take the place of import limits, including ruling that would permit the companies to receive an additional investment tax credit for new production machinery that conserves energy.

The tax proposals could be coupled with a relaxation of environmental and safety regulations affecting autos to boost the companies' cash flow, although it won't be easy to produce a package that provides the same relief as a cap on Japanese imports.

Yesterday, Lewis told the House Appropriations transportaiton sub-committee that there is no need to tighten the federal fuel-efficency requirements for automobiles once the curent 1985 deadline is reached.

Automakers are required to attain a fleet average of 27 1/2 miles per gallon by 1985, and Lewis said that the price of gasline will compel the companies to produce cars with milage ratings in the 30 to 50 miles-per-gallon range. "It's my feeling we don't need any more regulation. The free market's going to take care of this."