Got around to replacing my injector o-rings tonight. 3 of my injectors have had the pintle cap missing for ages with no ill effects. Installing the new lower orings I just use a dab of rtv to keep the oring and the small plastic ring above it in place. Reinstall went fine. Everything seats no leaks. I did notice that the new lowers seem smaller on the inner and outer diameter (not as fat) as the old ones and were a bit loose, but nothing crazy. Put everything back together and turned the key. It stumbled a few times and died. Cranked it again and it tried to run, clattered a bit and died. Didn't retry again.
In re-checking the injectors they seemed too loose in the LIM so I'm beginning to wonder if the Fel-Pro part # is incorrect for these cars now. I pulled the entire rail again and low and behold all 3 that were missing the pintle caps dropped their orings and the small collar into the intake .
Being rubber I see no issue with the missing orings. My question is can those small nylon rings harm anything? I would think that it would just throw them out into the exhaust and be done. I pulled the plugs on those cylinders and hooked my air compressor to a hose that fit snugly into the injector hole and rotated the crank by hand until that cylinder opened up and had a good stream of air but did not get anything to come out of the plug holes.
I really can't see that small ring causing damage internally, although that clatter makes me wonder. Anyone else ever run into this issue?