Scotty, et al.
I've found some horror stories online about some Lexus cars suddenly accelerating out of control and drivers unable to stop it. Did they ever find the reason these cars did this? Does this still happen? Would it be good idea to install a kill switch or panic button to cut off voltage to the engine should it happen to me in my '07 ES350 with 153K miles?
Your brakes should hold/stop your car. If they don't, get them fixed, as bad brakes are a problem all the time.
Your car also has a gear shift - you can put that into neutral as fast as you could flip a switch.
Toyotas had a bad batch of electronic throttle pedals a while back which, I guess have been fixed now. I never had a problem with a plain, old, throttle cable.
I once had a throttle cable snap in a <1yr old Suzuki. What a piece of junk that car was.. Had to crawl in 1st gear, all the way back.
Wow, that's a first for me. I've never heard of a throttle cable breaking before.
If the ES350 is drive by wire- input device data from the driver, (via shifter, steering wheel, brake pedal, gas pedal) is fed into a computer, wouldn't a defective position sensor/sender or corrupt computer render one or more of the controls ineffective in a runaway situation?