JDM D15B won't start

I have just installed a D15B engine in a 1993 Civic EX, but it will not start. We are getting 12 volts at the injector at all times, but the car will not turn over unless we spray stater fluid or inject gas into the throttle body. Please give some ideas as to what it could be. Fuel Rails gets fuel, but there is no fuel delivery from the injectors. Any ideas?

Check the return line pressure valve.... if the diaphram is stuck open, then it'll be letting all the fuel flow straight through without building enough pressure for the injectors to opperate correctly.

There should be at least 60lbs of fuel pressure at each injector.... so just test them and be sure you're getting the correct pressure.

That's the first thing I'd check at least