AutoPAC, the political action committee of import car dealers that made $1.4 million in independent expenditures in 1988 Senate races, has dumped $341,200 into the New Hampshire Senate race for television ads on behalf of the front-runner, Rep. Robert C. Smith (R).

The expenditures triggered an immediate attack by Democratic opponent John Durkin, who told a news conference yesterday the ads were an effort "to buy {Smith's} vote so the Japanese could put you out of work. These are the same Japs that staged the sneak attack on Dec. 7 {Pearl Harbor} and are now trying to stage a sneak attack on our election process in New Hampshire on Nov. 6."

Durkin later told the Associated Press he did not consider his remarks racist. But he added, "I don't want my kids sweeping up around Japanese VCRs."

Frank Glacken, AutoPAC executive director, said his membership includes dealers who sell European and domestic models as well as Japanese cars. He called Durkin's remarks "an indication of his isolationist and xenophobic perspective." Import car dealers employ more than 1,700 people in New Hampshire, he noted.

The AutoPAC ads, which were due to begin airing yesterday, focus on what Glacken called flip-flops in Durkin's voting record in the Senate in the 1970s.