I have a 2002 Mustang GT and dont know where to start I purchased used .The person I got from had put a used wiring harness allready on I believe all connectors are correct but not 100% sure Heres the problem when I try to start car will turn over but not start.I got someone to spray fuel in throttle body and car will then start for a few seconds then die.I purchased fuel pump but when I turn over again no start. Caint here fuel pump in tank coming on. I have worked on car some but mostly older car so not sure where to start checking first I know about inertia switch and fuel pump driver module and ccrm and how it works but never learned about the volts that come to and from them and have never started checking volts or anything like that and would appreciate the help on were to start at PLEASE HELP ME LEARN