I own a 1995 gmc sonoma and it left me sit earlier today. After working on it for awhile I discovered a few problems. The motor had no spark or fuel, I figured out the coil was bad and now it has spark and it starts on starting fluid but the tbi injectors aren't spraying. The fuel pump does prime but we aren't sure of how much pressure it's building. We put in new injectors and cleaned the entire throttle body and fuel is making it to the injectors but the injectors don't fire. Any ideas? Do the injectors require the 12 psi of fuel pressure in order to fire or is there another problem?