EGR clogging is a very common issue on the T6.
It wil need cleaning/ replacing at some point.
I had two flushes and a replacement under warranty.
At 50K we had the "All-In Extended Warranty Check" now infamous full check over 28/02/2022 50800 £0.00 ALL-IN check - VW - Passed ironically it failed at first. The Dealer come back in said - "Sorry mate, you got non standard suspension fitted - so its failed." tbc . . . . ...
www.t6forum.com
The EGR clogging may or may not contribute to blocked DPF.
Some have said engine wear and high oil consumption will block the DPF.
Assuming you are out and f warranty, the EGR is a replaceable £600 od part... Plus labour... So not cheap. But maybe cheaper at a local vw indy.
The adblue is a separate system.... that works with the dpf.... Smashing holes in the dpf is obviously not an official fix.... And assumed to be needed as the PDF may start to clog with soot now seeing as you are now not doing regents to clean the pdf? (Depending on what the delete does with adblu and regents?) - it may be making things worse? Possibly clogging the dpf till it's completely blocked?
As you found out, you need to go back to standard to have the original issues sorted out...
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How long has the van been modified? And the miles? - you might be able to recover it back to normal with just a new EGR cooler?
Keep us posted with any updates
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