I have a 2007 5.3 out of a silverado i just have the engine harness obd harness and the dbw harness.I have the engine harness c4 wired up so it gets all it's power and ground from what the schematic says the throttle plate moves when i move the pedal but when i crank it has no spark should i have spark trying to turn it on like this...coils,o2 sensors, everything has power and ground but just no spark is there something im missing what do i need to do to the ecm it should run i'm bypassing everything. thanks