I got a P0441 code on our '02 300M about 18 months ago. I left the battery disconnected for a while, and the code took until a month or so to return. Again I left the battery disconnected for a while,, but now the code has returned again.
I've read that it can be caused by an imperfectly sealing gas cap, so would buying a new gas cap be a good starting point? Other suggestions?
Perce