Fuel injector gone bad Options

[troth]

Vehicle was running great until I lost cylinder no. 2! Verified spark was good. Hmmm... must not be getting fuel. Swapped injectors with one of the good cylinders and was happy to see the issue moved with the injector.

I guess I'm going to shell out to have them all cleaned again. Even though I just did that less than 3000 miles ago. I say all because when I unplugged the injectors individually with the motor idling, each had varying effects on how it ran. So some of the others in addition to no. 2 may also be dirty?

But what could have caused them to go bad all of a sudden? One day it was good, but then the next day when I go to take it to work it's crap. I have read that letting the fuel level get too low can dislodge crud in the tank. It had about 3 gallons in it last time it was running well and it has certainly ran on less fuel than that before. Should the filter be replaced? Is it worth taking the tank out and cleaning it?

Lots of questions, but I am happy the immediate issue presented itself so quickly. I'm just trying to diagnose the root cause to avoid another $100 injector cleaning/test.