Mounting complaints of sudden and unexplained acceleration of some Mercedes-Benz automobiles has convinced the Department of Transportation to reopen an investigation into possible mechanical flaws in one model of the luxury car, a spokesman said Monday.
The National Highway Traffic Safety Administration said it will investigate Mercedes' best-selling model--the 300E--and will monitor complaints against other models of the West German-manufactured cars.
The inquiry was reopened at the urging of the Center for Auto Safety, a consumer watchdog group that filed a petition with the transportation agency alleging that Mercedes has one of the most serious rates of complaints of sudden acceleration among cars sold in the United States.
"We don't know what's going on with the cars," Mercedes spokesman Hal Williams said from the auto maker's U.S. headquarters in Montvale, N.J. "We're very concerned about the situation. . . . So far, we haven't found a defect that we can point to and say, 'This is the problem.' "
Williams said the company will cooperate fully with the National Highway Traffic Safety Administration.
"We gave them everything they asked for and then some the last time," he said.
All of the incidents examined in the first investigation, Williams said, could be explained by factors other than mechanical failure, such as poor maintenance or driver error.
The basic complaint is that the cars can accelerate out of control when they are shifted from "park" into "drive" or "reverse"--even if the driver has his foot firmly on the brake pedal.
According to the Center for Auto Safety, out of every 1,000 Mercedes 300E models sold in the United States, at least one owner has complained of sudden acceleration.
That rate is surpassed only by complaints lodged against the Nissan 280Z and 300ZX models and the Audi 5000, said Dan Howell of the center's vehicle safety staff. The Audi is already under investigation by the National Highway Traffic Safety Administration.
The Mercedes 300E, a four-door sedan that retails for about $43,700, was introduced in 1986. So far, about 35,000 have been sold in the United States, with about 6,700 of them in the Southern California region, according to Williams. The region includes Arizona and Las Vegas, but most of the cars were sold in Los Angeles and Orange counties, Williams said.
Southern California is the second most concentrated market for Mercedes cars, trailing only metropolitan New York.
Howell said the Center for Auto Safety has received 50 complaints of sudden acceleration in the 300E, resulting in 35 accidents and four injuries. Since 1984, all other models of Mercedes have had a total of 80 reported acceleration incidents, resulting in 65 accidents, 26 injuries and 1 death, Howell said.
"That's why this is getting so much attention," Howell said. "Once you get in the 1-in-10,000 range, you usually get a recall or some government action."
A spokesman for the National Highway Traffic Safety Administration said there are no hard and fast rules about incident rates leading to investigations or recalls.
"Some investigations have been opened on just one complaint," said Ron Defore, director of public and consumer affairs for the agency.
The National Highway Traffic Safety Administration said it has received 36 complaints about sudden acceleration in the 300E, involving 18 accidents and two injuries.
The apparent problem with the Mercedes cars was first examined by the agency in a low-level inquiry that was closed in January. At the time, only eight complaints had been lodged against the 300E.
But since then, the number of reported incidents has increased steadily.
"We're getting showered with accident reports," Howell said. "They just got too many accident reports to ignore any longer," he said of the government's willingness to reopen the case.
During the last 15 years, the National Highway Traffic Safety Administration has conducted 50 separate investigations of sudden-acceleration complaints involving about 20 manufacturers. In 1980 and 1984, Mercedes recalled more than 70,000 cars in its 450 series to replace an automatic transmission control-rod bushing that could cause the throttle to stick.
The Department of Transportation's Transportation Systems Center, a research group, is planning to conduct an independent study of the sudden-acceleration phenomenon on several makes and models of domestic and foreign-manufactured cars. Among the cars in the study will be the Mercedes 300E.