Make sure both sides of injector plugs have 12V on ignition. Make sure ecu gets constant 12V for battery wire and 12v on ignition for +B and +B1 pins.

If its all good and the engine has not been used in a while, the injectors are probably a little stuck. Best to try cranking it with a little start ya bastard in the intake. Eventually it will come good. Either that or drop the injectors in thinners for a few hours, should loosen them up (remove all seals off the first though).