Dirty EGR in a CVCA EA288???? Where is the carbon coming from?

[IDoSeaDoo]

Very puzzled: took the intake off my 2015 CVCA to dig out the blown turbo chunks and found the EGR ports very dirty and some mostly clogged. How can this be if it pulls clean exhaust from behind the egr?? The EGR cooler seems to not be leaking when I pressurized it (rudimentary test to find obvious leaks, didnt have correct piping to do a perfect test). I found some strange stains on the bottom of the dpf where the cooler is mounted. Might be coolant mixed with oil? It's greasy. Inside the dpf looks perfect and the exhaust post DPF has 0 soot. How are my egr ports so dirty with carbon? It looks just like Dirty, preDPF EGR mixed with oil vapors, but I can't find where dirty EGR comes from. The actual EGR valve I pulled off the cooler is pretty dirty too. Like something you'd see on a earlier model. How is that possible if the EGR is treated and has no soot??

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• IDoSeaDoo
• Sep 1, 2024

Dirty back side of intake charge cooler with blocked EGR ports

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• IDoSeaDoo
• Sep 1, 2024

Blocked EGR ports

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• IDoSeaDoo
• Sep 1, 2024

Dirty head, but valves are still clear

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• IDoSeaDoo
• Sep 1, 2024

Odd staining on the DPF where the EGR pulls from

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• IDoSeaDoo
• Sep 1, 2024

Bottom has this odd oily residue

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• IDoSeaDoo
• Sep 1, 2024

Back of the DPF is perfect, and finger comes away clean

 

[IDoSeaDoo]

UPDATE: I've been puzzling over this for a day or two, but finally realized that the exhaust manifold has an extra EGR port. What I thought was the pipe for the clean Exhaust from the EGR cooler is actually for that exhaust manifold port. The clean EGR goes into the turbo housing. I'm suspecting the oily residue on the DPF is from the blown turbo leaking oil down. doesn't appear that any of it made into the DPF as oil, as the DOC in front is just sooty.