A Virginia prosecutor called yesterday for an arson investigation in connection with the disappearance of a Montgomery County truck driver and wine importer who was believed killed in a fiery truck crash until a scientist determined this week that remains found at the scene were those of a pig.

Roman M. Leimer, who vanished after the Jan. 13 truck fire, had accumulated several debts related to his fledgling wine-distributing business in Jessup, Md., according to court records and interviews with business associates. Court files in Montgomery County showed more than $60,000 in judgments against Leimer over the past six months.

Prosecutor David N. Crump of Warren County, who is coordinating the Virginia state police investigation, said police are not ruling out anything, including a case of a missing person, arson, fraud or homicide. "It may be he's dead. Maybe he's not dead," said Crump. "He could have set it the fire . Somebody else could have set it. ". . . We just don't know."

Reached by telephone yesterday evening, Mrs. Leimer's lawyer said that his client is "quite upset."

"I think she is convinced he is dead," said attorney Richard Paugh.

Asked whether the 39-year-old Austrian-born Leimer might have disappeared on purpose, Paugh quoted Mrs. Leimer as saying: "He is not a man who would do something like that."

"Our position is that he just got totally incinerated in the fire," the lawyer said. ". . . with 10,000 gallons of gas and 5 to 6 explosions, I could see where no body would be around."

He said Mrs. Leimer is planning to petition Virginia officials for a death certificate.

The only remains recovered after the 90-minute blaze were three chunks of bone covered with charred flesh, later identified by a forensic anthropologist at the Smithsonian Institution as ham bones, and a wristwatch.

An expert on tanker truck fires said yesterday that in 13 years of investigations he has not seen a case in which a human body was completely incinerated. "I would be surprised if there were humans in that fire," said Peter Cooley, head of the accident investigation team of the University of Michigan's Transportation Research Institute. "If you have the remains of an animal, I would think that you would have equivalent remains of a human," he said.

According to an anatomy expert at the university, it takes about three hours at 1,500 degrees Fahrenheit to reduce an unembalmed human body to ash. Gasoline tanker fires customarily burn at between 1,800 and 2,000 degrees Fahrenheit, a spokesman for the research institute.

James O. Donahoe, a shock-trauma technician for the Front Royal Fire Department, said the remains that were recovered from the passenger side of the truck's cab were in three pieces that totaled about three pounds.

"What we found appeared to be burned flesh with bone protruding," Donahoe said. "The only thing we noted that was out of the ordinary was that the bones' edges were cut clean. There weren't any jagged edges."

The Virginia State Police said they will go to an Exxon terminal in Fairfax County today to reexamine the scorched hulk of the 8,900-gallon tanker that Leimer was believed driving the morning of the accident. The truck was found ablaze along I-66 near Front Royal at the bottom of a 35-foot embankment.

A few weeks before the fire, a court judgment was issued in Montgomery against Leimer for $44,000 he borrowed to open his wine business, Romax Inc. A second case was pending against Leimer for collection of a $17,000 debt a court had ruled he owed WMAL Radio for a series of wine commercials aired in the summer of 1981.

A Laurel attorney, who had met with Leimer to discuss the $44,000 case, said Leimer came to his office a few days before the crash. "He didn't seem terribly upset," said attorney Stewart Hurtt. "You know there are people who seem like a real wreck when they're having business problems. But he didn't."

He owed another $6,000 to Commonwealth Winery, according to David Tower, president of the small Plymouth, Mass., winery, who said he has made repeated attempts to collect. "He kept saying he was going to take care of it, and that the check would be in the mail the next day," Tower said.

An attorney representing Chateau Esperanza, a winery in upstate New York, said his client had filed a $1,600 lawsuit against Leimer two weeks ago for bills unpaid since last summer.

Leimer reportedly traveled to several wineries in New England last summer to make purchases for Romax, which sold a variety of Austrian and American vintages, including one imported from Vienna whose label carries a picture of a smiling Leimer hoisting a glass.

According to Tower and his business manager, Jeffrey Pontz, Leimer described himself as a former math professor in Vienna and the United States and a onetime member of the Austrian national soccer team.

In a wine article last spring in The Baltimore Sun, Leimer was mentioned as a former upholsterer.