I set the temperature on my oven, but then everything cooks too fast because I think the oven temperature is not being regulated and just continues to get hotter as time goes on. Is it the temperature sensor that is broken? (I am assuming it's a sensor because it's a digital readout, otherwise they usually use bulbs). If so, where do I get the part and how do I fix it? I do not have the owner's manual. Thanks!

Kitchen Ranges - Tappan - TGF363 Gas Kitchen Range