s13 sr20det injector firing problem

[duramax04.5]

So I have an s14 with an s13 sr20det swapped in it. We pulled it out of my friends car running and driving. I cannot for the life of me get the injectors to fire. I have spark, I have fuel set up correctly, the timing is perfect. Ive swapped out the ecu with two other working ecu's. Here's my problem I pull out the cas and spin it and the injectors fire but when I put it into the motor with correct timing they won't fire. I added an extra ground to the intake manifold. I can't figure it out ive searched for days and nothing. If someone could lead me in the right direction that would be awesome thanks.
Jake