andreigbs

Thanks for the update.

I think the trick was you cleared the codes, THEN started it up and let it idle a bit, to get its bearings and do all its self-tests. Having passed those, it then ran fine.

BTW, in most cases when you've got CEL and trouble code(s) in memory, it is standard procedure to replace the faulty part(s) and then clear all the codes before starting it up.

Good luck and be sure to update if anything changes.

FullMoonParty

Yes, thanks, I replaced the hose then cleared the codes. Multiple codes were thrown on the first and second drives after the hose replacement and code clear. Only after wiggling the ends of the new hose then starting the car and letting it idle for ten minutes did the code issue resolve. The wiggling is probably irrelevant and the idling is what did the trick. As I had taped up the old hose it was surprising - clearly even with the tape it was leaking enough to throw off the computer.

FullMoonParty

One more update. The car is running great again. No codes, no issues, and the rate of DPF soot build-up is massively slower. I had an oil change and got a sample for analysis with Blackstone - assuming it will show excess fuel from all the regens.

I believe the hose had started to leak long before it opened up enough to throw the code. The car had developed a mild hesitation when coming off and back on throttle at low RPMs, and the rapid soot build-up had been happening for quite a while before the code as well. My permanently installed scangauge has been the hero in allowing me to observe the change there with soot and regen frequency, and to deal with the codes mid-road-trip. And of course thanks for the people of this forum for sharing how to solve the problem!