I got the check engine light on my 2013 STS. The code is P1171, which I know is lean on cylinder 1. I do have the Power Commander 5 with the O2 optimizer, JT's air filter, and Akrapovic exhaust. It ran great for about 200 miles on cool days, but now the weather has warmed up I'm getting the check engine light. Anyone know how to adjust the mapping. I have only loaded the maps provided from Power Commander. I've never messed with changing the values in the map file.