Several questions remain:
I can't open any pictures associated with posts unless they are the "click on" type. The yellow box ones would be helpful. Any place to see good pictures of the MAP cleaning, removal of FCV and access to #3 and 4 glow plugs?
If a 1/4 " piece of the ceramic on the glow plug end fell off and I have not had any major problem with the engine except the 1263 code, do I assume it got expelled in the exhaust? Car runs great/smooth.
Removing the intake elbow and fcv is a medium sized job. Long extensions are a must. Also, get the intake gaskets. Check or order from idparts. There is a tech article on removal. I brought my tablet to the garage to help me.
More than likely, that piece is long gone. You are a lucky one. You probably have superficial piston and head damage like I do. But, your turbo could have been dinged up a bit. Mine was from 2 glow plugs. Just keep an eye on it.
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