why does my heat smell when I turn it on? I just purchased a 2001 chevy suburban ls 4x4 last night and the heat smells dirty or dusty I'm not sure, but the deal said it is fine! My kids got headaches and had to have windows down. dealer said he just replaced the oil pump and sensor, and had to take the engine apart to do so, so could that be the smell?? Plus the service engine light is on and it has almost 219000 miles on it.