EGR could be the culprit of oil in the intake valve.

If you do an EGR delete and oil consumption is at negligible levels then it's something you can live with.

This ought to be a fun thread. I'm staying tuned for this...

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1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.