Toyota hired some highly respected engineers -- one from Stanford and a team from a firm in Menlo Park known for analyzing engineering defects. They say a previous study seeking to pinpoint blame is unrealistic.
Engineers hired by Toyota have been doing their own research. At a news conference in Southern California, they criticized earlier work done by David Gilbert as faulty.
Gilbert, on the faculty at Southern Illinois University, testified on Capitol Hill two weeks ago blamed the sudden acceleration issue on electronics in Toyota's braking system.
"You cannot re-wire a circuit and expect it to behave as it was originally designed. By adding an extra component, Prof. Gilbert created a different pedal circuit than the one Toyota engineered," Stanford University Director of Automotive Research Chris Gerdes said.
Gerdes said the extra component was a resistor that would simulate a malfunction.
Other engineers hired by Toyota from Menlo Park-based Exponent Inc. said that the results were meaningless.
"We've tested other manufacturers' vehicles and re-engineered them and re-wired them in a similar manner to Dr. Gilbert's demonstration, and we got comparable results," Shukri Souri from Exponent Inc. said.
"Sometimes we create scenarios that logically make sense, but in the real world, conditions would have to be so ideal for that to happen," Skyline College professor Rick Escalambre said.
Escalambre reviewed the Toyota news conference, and he agrees with Toyota's engineers.
"Wires would have to touch. They'd have to be frayed and touch, which would be an obvious thing that any technician, yourself, looked at them, you could see wires are frayed," Escalambre said.
Gilbert responded to the criticism and said: "I will examine their expanded results and conclusions along with my own. I hope to complete my review within the next few weeks."
Others came to his defense.
"What he didn't do and wasn't asked to do was to do a deep dive into the entire mechanical and electronic system in the cars. That's something that Toyota and Exponent are doing, using tremendous resources," Consumer Reports Deputy Editor Jeff Bartlett said.
In the meantime, Toyota has been investigating claims that owners of 60 repaired vehicles are still having sudden acceleration problems. Toyota says it could be repairs not done correctly or completely.