Canada has decided against seeking a revision of its 13-year-old agreement with the United States on free trade of automobiles and auto parts.

Despite widespread criticism here, a special commission of inquiry said the time was not good for trying to renegotiate the pact with the Carter administration because of its "preoccupation with more compelling issues."

Criticism of the pact focused on feeling here that Canadians were not getting a fair share of parts manufacturing and research and development and that the pact in effect precluded the establishment of a domestic car manufacturer. All car makers here as subsidiaries of the Big Four U.S. firms.

The commission, led by Simon Reisman, a former deputy minister of finance who headed the Canadian team which negotiated the pact in 1965, was established four months ago amid mounting Canadian disasatisfaction with the agreement.

In particular, Canadian auto unions and parts manufacturers complained about an accumulated $7.5 billion deficit under the pact.

"Looked at from the Canadian side, the auto pact rescued Canada from the inefficient high-cost assembly and ports production associated with short runs, small scale and highly differentiated car models and parts who serve a relatively small and highly protected domestic market," Reisman said.

Nonetheless, Reisman admitted that Canada was losing badly on automotive parts, and he suggested a wide range of government initiatives to help Canadian parts manufacturers compete in the U.S. and other markets.

Reisman also noted that despite higher profits made by the Big Four automobile manufacturers on the Canadian side of the border, most research and development and a higher percentage of skilled jobs remained in the U.S.

"Although Canada's share of employment in the automotive industry is reasonably high, the employment in Canada is relatively more concentrated in less skilled jobs," Reisman concluded.

He added that 30.3 per cent of those employed in the U.S. automotive industry are considered professional or skilled workers compared with 24.4 percent in Canada.