2012 ford fusion SE 2.5L with 105k miles. It was idling rough, vibrating at stops, poor acceleration and misfires. I gave it a tune up, with spark plugs, ignition coils, serpentine belt/tensioner, oil/filter change, removed, cleaned, recalibrated the throttle body, removed and cleaned the fuel injectors. Now I only have misfires when the AC is on. The AC seems to run good. No noises. No codes.