Bought my 2013 st from Nissan 2mos ago. Have the wierd idle and stalling thing which went away because I squeezed the area in the harness that had the splices. Idle was changing when I was doing this and then stabilized. 2 weeks later idle slowly acting up again. I know it's the harness. Nissanhad the car 2 x but could not find anything wrong. Ford says they performed the wire harness for previous owner and I need to pay for diagnostic and that would be deducted from repairs if they find an issue. Does Ford have any obligation to fix this especially since I bought it preowned from another dealer?