i looked inside the fpr and i see what looks to be like two o-ring one black and another red. when i pulled it off the hard line i thought i saw a 0-ring fall but i cant find it. is there a o-ring that goes over the hard line. i think im missing something cause now its leaking there

 

If your sure you saw something fall when you pulled it out then yes there prob was an oring there.. I cant say becuase i dont have the FPR and i have a hard plastic line that connects to the rail.. I didnt have an oring there... Someone else will chime in and give you the correct answer

 

Also, when I had the leaking problem with my fpr, my input o-ring got ripped. I went to the auto parts store, found the closest o-ring size to it (which was slightly smaller, you will never find the correct size) and got two of them. Doubled them up and that stopped the leak.

 

I know this thread is kind of over, but mine started leaking on the return side of the fuel regulator after replacing a fuel injector. I guess the O-Ring got fatigued and isn't making a seal anymore, I'm going to try the injector o-ring first, if that doesn't work I will just go to a parts store and match up the o-ring with a simular one like said earlier. Thanks guys!