Hoping someone else may have experienced this and could shed some light. I'm getting code P2187 indicating that air/fuel mixture is too lean at idle (had previously been getting P2177, same indication). The thing is it's difficult to take it seriously because the car runs perfectly and the CEL comes and goes without me trying to do anything about it. Since the car runs so well I don't know what I could even try but it's just annoying to see that CEL come and go.

 

There is no such thing as an intermittent DTC/CEL. You need to do a proper diagnostic scan at the OBDII diagnostic connector (no blue tool scanning device) look at the pending files and also your monitors. I am sure you will find some better information.
Once you have found this information and noted it then clear any and all DTC(s) reset your monitors and drive until the check engine light is activated and retrieve the DTC a quickly as possible. It would also be good to check in the pending file and monitors again and note changes from last reset.

Then return and post your information.

 

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