while you do need a special socket to remove the injectors it is not that hard to do it and it might be the best next step. The socket only costs about $25 from a dealer and they are also available aftermarket. I'm not 100% sure but I think the hole from the injector is a little larger and goes right into the same chamber where the tip of the GP sits so you might have more of a chance of getting it out from there - or blowing it out through there with compressed air. Others with more experience with the pre-chambers on these engines might chime in...

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Marty D.

2013 C300 4Matic
1984 BMW 733i
2013 Lincoln MKz