The DPF warning light appeared on the dash for the first time with no other issues at all with car. I checked with my handbook for advice which l followed to the letter reset the regeneration system but this did not happen. The car filled the motorway white smoke and the engine racing leaving in a very dangerous situation along with other road users.
This is well documented here: www.honestjohn.co.uk/carbycar/mazda/6-2008/?sectio...d As the DPF fills with ash, extra fuel pumped into the engine to regenerate it cannot do the job and instead sinks to the sump, raising the sump level to a point where a compression ignition engine starts running on its sump oil and cannot be stopped except by force-stalling which will probably damage it anyway.
Answered by Honest John on