hey can u guys tell me what u think caused this "streak" on the middle (black) part of the injector? it seem to run downward but nowhere it can eak from except the seam between teh blue and black...and what is the injector O ring? the orange ring on the bottom? that is the top ring and it stops there...also would gas cause a discloring liek this?...or could this just be somehting spilled on them or just something rubbed it off...(2 injectors of 8 have this and this one also has some on the other side....pic will basically tell the story. thanks in advance