Some of these small parasites have been mutating and are now resistant to many over-the-counter medications.
Iowa Republican Senator Chuck Grassley is looking into whether federal agencies were too quick to wrap up the investigation and clear Toyota over safety concerns.
He has written a letter to the National Highway Traffic Safety Administration, the agency that oversaw investigations into reports of thousands of cases of sudden acceleration in Toyota cars, including the case of the California Highway Patrol officer and three family members who were killed in 2009 when they could not slow down their racing Lexus.
Safety advocates said Toyota’s electronic systems might be at fault, but NHTSA said studies by federal agencies including NASA found nothing wrong with Toyota’s electronics.
In his letter to the agency, Senator Grassley says “key questions questions about the cause of unintended acceleration remain unanswered.”
Senator Grassley’s call for more investigation comes even as another car maker, Hyundai, faces a possible law suit charging the company with using misleading fuel economy claims in its advertising.