Unless Congress gets on the ball, some of President Reagan's favorite federal workers--the meaner-than-a-junkyard-dog inspectors general--may find themselves out on unpaid furloughs this summer, rather than sniffing out waste and corruption.

Although the threat of furloughs is fading fast in most agencies (the exceptions are the Office of Personnel Management and the Government Printing Office), many agency IG operations will have to be cut back unless Congress approves pending special supplemental money bills.

Full funding for some IG functions, which are intentionally kept separate from regular budgets, has still not been approved even though the salary and expense money crunch for agencies the IGs are supposed to oversee has eased.

Last week, for example, the General Services Administration announced that thanks to what it called superhuman penny-pinching by its top management, it was scrubbing plans to furlough its 31,000 managers, clerks, contract experts and housekeeping specialists.

But GSA--like a lot of other agencies--forgot that its IG personnel are paid out of a separate account that doesn't have enough money to pay those workers for a five-day week through the rest of this fiscal year.

Several IG supplementals, like the GSA bill, await congressional action. Even though most people think that the money will be approved, agencies are drawing up furlough plans in case Congress gets bogged down or goes off on another vacation without paying the bills.