Here is where you are going to learn how to diagnose and repair your ill running ride so grab your toolbox, a pencil and paper, hit the link I'm posting and read through it to get an understanding of what you have to do and how you do it. Get stuck or have any questions post them in this thread an the members here will help you out.
Updated 26-Oct-2019 to clarify creeping idle RPM increase as the car is being driven. Many of you are familiar with the "Cranks OK, but No Start Checklist for Fuel Injected Mustangs" checklist and the No Crank Checklist. They are very effective in finding and eliminating the problems by use of...
forums.stangnet.com
It's free and if you do it step by step you will be motoring down the highway.