Chevrolet Repair: starting problems

Question
QUESTION: my son and I put a new motor in his 04 chevy Silverado the old motor ran before we changed it but know the new motor will not start it will not turn over from the key getting fuel but not to the injectors

ANSWER: MORN JOHN, YOU SAY THIS WILL NOT TURNOVER. THAT MEANS TO ME THE STARTER WILL NOT CRANK. AS IN TURN THE ENGINE OVER. DO YOU MEAN IT WILL CRANK BUT NOT START, ?? I GUESS I AM GOING WITH THIS, SO IF THE ENGINE CRANKS AND THERE IS FUEL AT THE FUEL RAIL BUT THE INJECTORS ARE NOT OPENING THE FIRST THING I WOULD DO IS CK ALL THE FUSES IN THE ENG BAY AND UNDER DASH AREA..USE A TEST LIGHT TO CK FOR POWER ON BOTH SIDES OF THE FUSES WHEN THE KEY IS TURNED ON..ARE YOU SURE YOU HOOKED UP AND WIRING HARNESSES CORRECT ??? YOU ARE THROWING ME A CURVE BY SAYING IT WILL NOT TURN OVER FROM THE KEY BUT YOU SAY THERE IS FUEL PRESSURE..I AM CONFUSED..GET BACK TO ME ON THIS SO I CAN BETTER UNDERSTAND YOUR QUESTION..I WILL BE HERE FOR ANOTHER 2 HOURS...TOM...

---------- FOLLOW-UP ----------

QUESTION: Tom ,If you jump the starter it will turn over but will not start, but not from the key. It is getting fuel to fuel rail but not to the injectors. Put in a used fuse panel under hood. checked the wiring made sure they were in the right places.

Answer
HI JOHN, CK THE RELAY FOR THE START/INJ. SO WHEN YOU TURN THE KEY TO CRANK THERE IS NO POWER ON THE PURPLE WIRE GOING TO THE SOLENOID,ALSO NO PULSE TO THE INJS TO OPEN THEM...GET URSELF A 194 LIGHT BULB BEND THE TANGS STRAIGHT OUT AND PUT THE BULB IN ONE OF THE INJ HARNESSES THAT YOU ARE GOING TO UNPLUG..NOW HAVE SOMEBODY CRANK THE ENG OVER,,THE LIGHT BULB SHOULD FLASH FOR PULSE TO OPEN THE INJ'S.IF NO FLASH CK THE ABOVE [FUSES AND RELAY..IF ALL OK,MAY HAVE PCM ISSUES OR AGAIN SOMETHING NOT CONNECTED.... THIS WILL BE IN THE UNDER HOOD FUSE BOX PANEL.IF THIS WAS OK BEFORE AS YOU SAY SOMETHING DID NOT GET HOOKED BACK UP OR A FUSE OR RELAY BLEW..LET ME KNOW WHAT YOU FIND AND GOOD LUCK TO YOU,,,TOM..***************************************************************************************************************************************************************************************
PS JUST THOUGHT,, I WANTED TO ADD THIS,DID YOU BY ANY CHANCE SHORT A POWER LEAD OF SOME KIND TO GROUND ?? THIS COULD SEND A SPIKE TO THE PCM CAUSING IT TO FAIL...YOU COULD CK FOR VOLTAGES AT A FEW OF YOUR SENSORS TO SEE IF THERE IS A 5 VOLT REFERENCE WITH THE KEY ON FROM THE PCM..IF NO VOLTAGE EITHER THE PCM HAS FAILED OR AGAIN A HARNESS IS NOT PLUGGED IN OR SHORTED OUT.....LET ME KNOW HOW THIS GOES...TOM..