1. The CEL is unrelated to the brakes.
2. I still think its the caliper, from the way the noise sounded...but it could possibly be a pad wearing out. However, I don't know why the inner pad would wear more than the outside, in theory they should wear evenly.
h:
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2015 Ford Mustang GT Fastback - Ingot Silver - 6M - Performance Package - Gibson Catback, JLT CAI, FR 47lb injectors, BAMA E85 tune, Eibach Sportline, BMR wheel hop kit, UPR oil separator, Steeda shifter bushing/bracket
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