This happens on my Corolla, which is quite old now. If I floor the gas on the highway, it continues to accelerate for a while after letting go the gas. It fre

This happens on my Corolla, which is quite old now. If I floor the gas on the highway, it continues to accelerate for a while after letting go the gas. It freaked me out the first time. The folks in the shop told me that I have a build-up of carbon on the throttle body, which causes the throttle to be sticky. They offered to clean it off, but I couldn't be bothered to pay for it. There's definitely nothing wrong with the pedal or any electronic control systems, it's just a car that needs tuning up.