More motor vehicles were recalled in this country for repairs of safety defects last year than any other year in history-and the new year was started yesterday by a government recall involving an estimated 40,000 1975 model Volvos.

The Department of Transportation's National Highway Traffic Safety Administration (NHTSA) said an estimated 12.6 million vehicles were involved in 1977 recalls, a sharp upward swing from the three previous years. The previous high-some 12 million vehicles-was in 1972. From 1974 through 1976, the vehicle recalls averaged less than 3 million a year.

According to the government agency, last year's recalls involved 195 separate campaigns by U.S. manufacturers involving 10.7 million vehicles and 49 recalls by foreign car makers involving 1.94 million.

yesterday's recall of Volvos is related to two accelerator/throttle-system problems which could prevent the driver from controlling the auto's speed.

NHTSA identified the cars as model 240s with B20F engines, manufactureed form August 1974 to May 1975. The problems involve plastic coverings for the throttle cable and fraying of the cable, which could result in increasing or holding steady the auto speed.

If speed increases without control, drivers should turn the ignition key to "off" (not "lock") and drive to shoulders of the road, NHTSA said.

Major auto recall campaigns last year included more than 1.3 million 1973-1976 Dodge Darts and Aspens and Plymouth Volares and Valiants that were stalling, power brake booster problems in 2.2 million 1976 General Motors Ford Motor Co. vehicles with breakable fan blades.

Some 1.4 million 1970-1977 Honda motorcycles also were recalled last year to correct unsafe gas lock caps.

An unrelated product recall announced yesterday involves imported Christmas light replacement bulbs made in Taiwan and brought to this country by Le Gran Imports, Long Beach, Calif.

The Consumer Product Safety Commission discovered a defect in some bulbs which could create a fire or shock hazard, the agency said. Bulbs involved are labeled as No. LC-7005P, size 7 1/2. The words "Christmas lamps" and "LeGran Imports" are on the packages, which were sold nationwide at less than 75 cents for a package of five.