Seeking Advice on Resolving EGR Issues and DPF Regeneration Failure in a 2006 Volvo S40

Hey there, Your issue sounds quite familiar. I had a semi-related trouble with my 2008 Volvo V40 a little while back. Just as a disclaimer, I'm not a pro mechanic, just a car enthusiast with a bit of experience under my belt. In my case, the root cause was damaged cables on the electric changeover valve. Once my mechanic pin-pointed the issue, I paid around 155 Euro and that sorted everything out. It sounds like your issue might be more complicated than mine but from my experience, once those cables are okay, a lot of the symptoms alleviate. Definitely have them checked out at your workshop. Also, could you let me know if your car's service history has been kept up to date regularly? or if there have been any recent changes or happenings with your Volvo? These details could help narrow down the issue. Hope this helps in some way! Good luck with it!

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Hey there, Thanks for the quick response and sharing your experience! Really appreciate it. I certainly will check the cables on the changeover valve as suggested. As to the service history, my Volvo had her last major service not too long ago at 115,000 KM. A general check-up was done and she was running fine post that. It's been a little over 1,126 KM since that service and there haven't been any major changes or incidents to note besides this issue croping up. Going to try and get a more professional diagnosis on the car soon, with a specific focus on the EGR and the cables. Hopefully, it's something simple like in your case. Thanks again for the helping hand!

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Hey, Great to hear you’re keeping an eye on the service history! That's super important. Since your car just had a service recently, the chance for it being a service-related issue is less likely. The EGR system and the cables – exactly where you're looking – absolutely sound like the right spots to have a deeper look. Failure to regenerate the DPF can indeed cause black smoke and a loss of engine power, and this can be due to a damaged cable, as in my case, or a EGR valve issue. You might also want to look into the hissing noise. In some cases, it hints towards a hole or leak in the exhaust system, contributing to the strong exhaust smell and potentially the black smoke. Hope this gives you a somewhat better understanding of what might be going on. Can't wait to hear some updates from your more professional check. Keep the rubber burning! Good luck & Cheers!

(Translated from German)

Hey, Your advice truly resonates with my gut feeling, and confirms that I'm on the right track. I will absolutely look into everything you've mentioned, including the possible hole or leak in the exhaust system. I'm truly relieved to have this guidance from someone who has been there before! I'll make sure to keep you posted on how things develop after my visit to the mechanic. Thanks once again, couldn't ask for better support! Until my next update, take care and cheers!

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