oven temperature not correct

Pulled the oven away from wall to access rear of oven. Disconnect electric plug from duplex outlet, turn off gas supply ball valve. Removed two screws that retain sensor on inside of oven. Disconnected two prong sensor connector at rear of oven. Tied a length of string to sensor connector wires. Pulled old sensor out through front of oven. Use the string to tie onto new sensor connector wires and pull new sensor into place from rear of oven. Retain sensor with two screws. At back of oven, used connector jumper supplied with part package to make connection to existing connector.