Driving along highway and suddenly my car begins to accelerate without pressing on gas pedal. acceleration is stuck, i can't stop the car other than by riding the brakes or turning engine off. i reach speeds up to 90 miles an hour. when i cut the engine off, it causes loss of power, but luckily not steering. turn engine back on and engine redlines (clutch let out). i pop clutch back in and car begins to accelerate again. turn hazards on, cop then pulls up behind me telling me to pull over. fear and anxiety compounded, but car still will not work. i cut the engine and highway patrol guides me over to the right shoulder. cop is forced to push my car since it cannot continue on its own. car towed in and dealer said a rock was wedged on the throttle return spring causing throttle to be wide open. rock was removed and dealer says car is functioning. the safety issue is with how the rock ever got there. that should not be happening, even at 1 in a million chance. i know my life and the life of my passenger were in danger. cop could probably attest to that as well. *ak