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I have 2014 F 90. It has the classic ISC symptoms. I have replaced the ISC and TPS. The problem still exists. Sometimes it will start and hold 700 rpm. At 700 it idles clean and perfect with no smoke or miss. Sometimes it will barely idle at 500. Sometimes it holds around 1,100. And sometimes it idles at 2500 RPM. When I run the 2 second test with the YDS software and it running 2500 it will cycle the ISC and settle at 700. If I run that test and it is barely idling it will stall as it cycles. Could it be that my replacement ISC is bad? Do I need to run that 30 minute test?