Here's a bit more info on this topic. The cam sensor is used for injector timing, like pdqford said. However, if the pcm doesn't see a cam signal, it'll go into a "bank-fire" mode and hit more than one injector at a time. Also, a short to ground at the v-ref circuit will cause the CEL to stay dark at koeo. If the cel illuminates at koeo, and goes out during cranking, the pcm is recieving a crank signal. Also, the presence of spark confirms crank signal. The injectors are powered from a common source and the pcm supplies the ground. Check for power at the injectors (like somone else said). If present, check for a "break signal" (intermittant ground) on the pcm side of the injector connector during cranking. Could be a bad pcm, wiring problem, or even 6 bad injectors.
