Have the injector lines ever been completely off? Or the crossover tubes removed?
The last time I swapped the injectors out on my 24valve i had a similar issue. I found that all the seals on the crossover tubes had basically rotted away causing air to get into the return fuel cavity (and probably back to the injectors). It took 10-15 seconds to get it to start. A few tubes were leaking so bad I didnt have to crack them to bleed. Just leaked fuel allover the intake.
