Well, you might be right.......I don't know anymore. I get a CEL with my car almost 100% stock (K&N drop in filter and a forge BPV) in the cold weather. I do not think the people at Mazda expected these cars to get driven in temps below 10* like we get here in New England. It is fine when temps are 35* and above but when it hits the 20s forget it. CEL time. It's a lean idle or what ever code. I have a Ford dealer down the street and they have read and cleared the code 5 times now. Lately I just do not even bother with the dealer. I just unplug the battery when I get home and it's gone. I am afraid to do any more mods at all to this thing at this point. It shows the CEL if I friggin Fart!!!!!!!!