Radiation from space long has affected airplanes and spacecraft, and is known for triggering errors in computer systems, but has received scant attention in the auto industry.
The questions show how deep regulators and automakers may have to dig to solve the mysteries of sudden acceleration. Toyota
says it is fixing mechanical problems -- floor mats and sticky pedals -- that explain sudden acceleration in 13 models and 5.6 million vehicles.
But at least half of more than 1,500 recent complaints to regulators involve other models, raising questions whether Toyota has fixed its problem.
An anonymous tipster whose complaint
prompted regulators to look at the issue said the design of Toyota's microprocessors, memory chips and software could make them more vulnerable than those of other automakers.
"I think it could be a real issue with Toyota," Sung Chung, who runs a California testing firm, said.
Toyota, which has led the auto industry in using electronic controls, told the Free Press its engine controls are "robust against this type of interference."