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Can I leave my car running overnight to clean the DPF?

I have a 2010 BMW 320d Efficient Dynamics that has done 102k miles so far. The garage I gave my car for servicing said there was a yellow warning about my DPF. They suggested they can clear my DPF filter by putting it through 600 degrees C heat treatment for £200. If that doesn't work, the replacement cost is about £2000. I do very few local miles since the last three years. Someone suggested that I could do a long drive and that would clear the DPF. Someone else suggested I can buy a spray that can clear the DPF. How long should the long drive be?

I am not in a position to take the car on a long drive. I won't have the time. Can I leave the car running overnight - will that have the same effect? Or would I be better off using a spray?

Asked on 14 March 2019 by mad_about_wheels

Answered by Honest John
By 102k miles the DPF will be filling up with ash from the soot it has been burning. It might be possible to chemically clean it out by the Ceramex process. This means removing the DPF and sending it to Ceramex, with all work documented. It probably will work, but is not guaranteed and costs about £400. Your local garage will be suggesting an "in situ" treatment that is less likely to work. A long drive might clear soot. It won't clear ash.
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