A few months ago, I replaced all the o-rings on the fuel injectors.
When I did this, I oiled each o-ring, to get it well seated.
Everything worked fine for a few months. All of the sudden, about 2
weeks ago, I started smelling gas after driving my XJ. After further
investigation, I found that one of the injectors is leaking. It seems
like it's coming from the upper o-ring (that goes into the rail). I
pulled the rail off to check the o-rings. Everything looked fine, so I
oiled them up a little, and put the rail back on - still leaks. The
retainer clip at the top of the injector is tight, the injector seems
well seated. I can't see how this could still leak. Any ideas?
Could the injector itself be leaking?

Thanks in Advance
John