Stove was converted to propane when we purchased it. Whenever the oven is used. it emits a strong odor like a car exhaust. Once is has reached full temp, the fumes are hardly noticeable. I have removed the panel just over the burner to check it out, and the underside is covered with soot. However, when observing the flame with the oven floor removed and the panel installed, the flame looks blue and normal. This has been happening from the beginning, but seems a little worse now.