you use the y8 manifold if you did there will be a fitting right between the 2 and 3 cylinders you have to plug that if you used the z6 mani you will be able to see a little hole in ur block between the 2 and 3 cylinders. also is your injector box plugged all connections securely together, you have to check over the electrics very well. can you hear your fuel pump working, are the plugs still good, there could be many things experiment and let us know.