RARELY HAS ANY regulatory agency got itself into as much trouble as the Federal Trade Commission. Some of the trouble is deserved. So Congress is quite properly trying to deal with the FTC's excesses. But the efforts now being made by both houses threaten to destroy the effectiveness of what is one of the government's most active and creative agencies.

The proposal pending before a Senate subcommittee to withdraw the commission's power to prevent unfair commercial advertising is an example. That power, granted to the FTC 40 years ago, has been used to curtail unethical and unscrupulous advertising. While it has occasionally been used in a way that has angered particular corporations for advertising.While it has occasionally been used in a way that has angered particular corporations or advertising agencies, its existence has been beneficial to both manufacturers and consumers. The FTC's work, as much as anything else, has forced facts into advertising and pure fraudulence out.

The purpose of taking this power away from the FTC is apparently to force the termination of its investigation into television advertising aimed at children. While that investigation should be abandoned, this is not the way for Congress to force the issue. By limiting the FTC's power to prohibit advertising that is both false and deceptive, as the proposal before the subcommittee does, Congress would open the door to a flood of ads that may be true but deceptive or patently unfair and misleading.

The approach taken in the House is much more straightforward. The House has voted against a regulation that would have required funeral directors to provide itemized price information and prohibited them from giving misleading information on legal or cemetery burial requirements. That regulation seems so innocuous and -- in light of what has been documented about practices in some parts of the funeral business -- so badly needed that the House should not even have reviewed it. But the attack on the regulation was at least not cloaked in language that would alter substantially a large part of the FTC's jurisdiction.

There are other proposals being pushed in the Senate that have the same fault. They change the FTC's rule-making authority and procedures in order to limit particular proceedings. A better course for Congress would be either to order the FTC to drop those investigations it dislikes or to wait until the agency has finished its work and then review the results, overturning them if a majority wants to.