maytag oven doesnt bake right

the elements both work. i tested the temp sensor had 1090 ohms at room temp
set over to 350 degrees it tested 1610 ohms had thermometer in oven it read 350 went down to 325 but never went any higher or lower. one time before i test everything it went down to 300 is there anything esle i can check or replace. please help beforei have to by new stove. thanks.