Injector question

2003 sprinter, 235k miles.
Swapped out injectors for rebuilt ones, and now have a solid miss and loss of power. There is no chuffing or leaks, but I noticed that the electrical portion on the top where the injector plugs into the harness is loose and swivels. There also appears to be a slight fuel leak between the piezoelectric portion and the injector body. Any idea if this could be the cause of my woes?

Swiveling is not normal, sounds like your "nut thing" on top is loose (probably best case scenario vs. other things that might cause this)

I would not tighten it without removing the injector so you can counterhold it properly on the flats where the clamp down paw sits. And look up a torque spec (I'd call an authorized Bosch rebuilder such as http://ocaladiesel.com/ to discuss your issue and the torque spec)

If the nut is loose, the rebuilder didn't torque it correctly unless you loosened during install, so I suspect the calibration could be wrong as well. I'd send all 5 back and ask for a re-do if you have time. If not, check the torque on all the nuts.

I don't remember if loosening this nut would also cause a leak, maybe someone who has taken one apart more recently can comment on that. I'm about 90% sure it will cause "swiveling" though.

IIRC Om612 engines do not code injectors to ECU, only OM647 T1Ns do

Thanks- post edited- the images I see looks like the injector design is similar, so the nut thing might still be the case

Yes, this is what I was worried about, thanks a million guys. I'm having them send me a replacement. Hopefully it explains the miss. I can swivel it completely around by hand until it stops against the valve cover and the injector feed line on the other side. I'll report back. Thanks so much.

Another thing to check is the fuel return line fittings. The OEM ones are plastic, which can crack or break with multiple removals. The o-rings may also be old and brittle. This can cause some fuel leakage. The replacement set from Europarts are brass and will last forever. They sell them as an assembled set with hoses, but someone found a source for just the brass fittings online.

I'd be worried about the quality of these rebuilds. They are supposed to test the injectors after rebuilding. That should have shown up during that testing.