We own a 1999 Oldsmobile Alero. A month and a half ago we noticed a weird odor emanating from the trunk. For a while we thought it was mildew, though it gave my wife a headache once or twice. While servicing the car for an unrelated problem the technician suggested it was mildew. As the weather warmed up the problem disappeared. With the return of cold weather last week the smell reappeared with a vengeance. We feared it was exhaust and put a carbon monoxide detector in the trunk which registered positive. We took it to a GM service department and they located the problem as a faulty rear defrogger antenna control module. It was heating up and melting the plastic shell of the module. We're glad they located the problem and fixed it, but are worried that other people may encounter this and not know what it is or not get it checked, like we did for a while.

- Rochester, NY, USA