So I have a Mac cold air on the truck. about six months ago I get the check engine light, after resetting it I (like an idiot) took it to ford. $70 later I get a call telling me, and I quote "need to put the stock air box back on" because my aftermarket intake is throwing the code. I resetit one last time and it stayed since. A couple of weeks ago I had a new transmission installed and now the light is back. I'm not sure what the code was, but I do know it said running lean in bank1. Any ideas. Thanks in advance.
