Oven temperature was off a few months ago. Seems it was around 100 degrees less than the control knob stated. I replaced the temperature sensor and still have the same problem. I can see the oven fire glow at the bottom but never really kicks in.. also sometimes smell gas?? Top burners and broil work fine. What tests can I do to determine what is wrong? Already wasted $50 on the sensor and am debating to buy a new oven. PLease help!