Accelarator sticking and overheating gauge going up and down. What is it?

Sorry, No one could possibly diagnose a vehicle based on that information ! A vehicle inspection & diagnostic would be required.

That happened on mine, it was the cable that connects the pedal to the gas, I had a short on the electrical (squirrels? chewed through the wires?). Early in the morning, I heated it up, I guess some frost melted, caused the short, and heated the cable so it forged it together. My gas was always on.