The warnings, from State Farm, which maintains a vast store of crash data based on its customer base of more than 40 million, followed a stream of consumer complaints about the alleged defect. Regulators received the warnings more than a year before they pressed the automaker to issue recalls affecting millions of cars and trucks.
Congressional investigators are now focusing on whether the government reacted properly to years of complaints and other evidence regarding the acceleration problems.
The insurer's warnings to the National Highway Traffic Safety Administration are likely to add to criticism that the agency missed or overlooked signs of trouble.
"When we see something that might be helpful, we pass it along," said Dick Luedke, a State Farm spokesman.
Luedke declined to go into detail about the alerts, except to characterize them as "numerous" and not "everyday" occurrences. He directed further questions to NHTSA.
NHTSA spokeswoman Karen Aldana said the agency received a claim letter from State Farm in September 2007 regarding a Camry crash.
"Our investigative staff reviewed the report and added the information to our complaint database," she said in a statement.
Aldana offered no comment on the other alerts from State Farm on Toyotas.
The State Farm warnings in the Toyota case echo ones the insurer made more than a decade ago about accidents involving Firestone tires and the Ford Explorer. When congressional investigators at the time discovered that the agency hadn't heeded the State Farm warnings, the furor in part led to legislation that created an "early warning" system for auto safety.
"If the question is, has NHTSA learned its lesson since then? I don't think it has," said Joan Claybrook, NHTSA administrator from 1977 to 1981, who testified at the Ford-Firestone hearings.
In 2000, the agency's treatment of the Firestone and Ford warnings outraged some members of Congress. After hearings that year, Congress passed the TREAD Act, which was supposed to have the safety agency create an early warning system to gather and analyze more information on auto safety to eliminate defects sooner.
The information was to have included defect-related claims involving death and injury, the number of paid warranty claims, and other reports from manufacturers.
But a 2004 report from the Department of Transportation's inspector general found that cost estimates for the project had increased and that the computer system "does not have the advanced analytical capabilities originally envisioned."
The report also noted that much of the information would not be made public. Public interest groups have since sued in efforts to make the system more open.
"Nevertheless, NHTSA now has much more information from which to identify potential safety defects than it ever had before," the report said.
Randy Whitfield, a Maryland consultant who has studied auto safety and whose work has been cited by NHTSA, said the TREAD Act and its early warning information have proven useful for analyzing car safety.
Using the data, he calculated two years ago that the Toyota-made 2007 Lexus ES 350 and the 2007 Toyota Camry had an unusual frequency of injuries due to speed-control problems. The information was posted online in October 2008.
He suggested that congressional investigators look askance at any claims by the agency that it lacked the information to crack down earlier on Toyota.
"This time, the [investigators] shouldn't let NHTSA say they didn't know what was happening because they didn't have enough information. . . . We shouldn't just let them kick the can down the road."
Claybrook, who appeared at the 2000 hearings and is scheduled to testify at a hearing this week, similarly criticized the agency for failing to use what power and information it has to protect the public.
"It has to do with the enforcement mentality," she said. "The agency has incredible power, including subpoena power. But if the administrator is not interested in whether the law is enforced, then these investigations just fall by the wayside. I've seen it over and over and over again."