About a year ago I got a recall notice that mentioned the EGR valve, but it was for a software upgrade. They'd fixed a bug in the code that was causing a "lean burn" or something to that effect. The extent of my engine knowledge is that I know how to change my own oil, so I just smiled and nodded.

I went and got the software upgrade for free, and my MPG went down after that for a while before coming back up.