+1 on sounding like a fuel pump. You're probably getting misfires due to low fuel pressure.
As for injectors, why do so many people jump to the "bad injector" diagnosis? It seems that every car hitting the U-Pull-It yard has the injectors yanked in the first few days. I've owned numerous fuel injected cars (with high miles) since the mid-1980s and never had an injector go bad. I bought the Kent-Moore zapper to test injectors almost 20 years ago and have yet to find an injector so far out of spec that it must be replaced. I did once work on a Toyota or Nissan (can't remember) that had a completely dead injector.
Is my experience unusual?