A year and model would really help. You could try and Google the information needed. Try it.You could also pay for programs like Direct hit, Mitchell, All Data. Hope this helps.  Some librarys have vehicle information for free through E resourses but you have to join which is free in Canada and  other places i am sure. Hope this helps. Keep smiling

Found another that I forgot about    bbbind.com  car repair as well as wiring on a huge amount of vehicles and its free

 Go to autozone.com and create a free accoun and you can get such info.

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What's your fuel pressure? Since it starts when you spray cleaner in the throttle body you can rule out crank sensor.  CSPI Vortec vehicles may not start if fuel pressure is below 50 PSI, it is very possible that you have a weak fuel pump, as poppet style injectors require at least that pressure open.