When an electronic fuel injector is good, we don’t have much reason to pay any attention to it. As long as it’s operating properly and delivering fuel as it should, there is a natural tendency to leave well enough alone. But when a fuel injector goes bad, it can cause a variety of driveability symptoms that can be just plain ugly. It becomes pretty hard to ignore the injector at this point. The problem is, some of these symptoms may not immediately appear to be caused by faulty fuel injector. Even an experienced diagnostician can be lead down the wrong diagnostic path, which can cause wasted time and unnecessary parts replacement.