Mazda 6 - Mazda 6 DPF light help!

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Sat 17 Jan 2015 11:35
Mazda 6 - Mazda 6 DPF light help! - Rachael_Kell

I have a question. My dpf light is flashing on my 57 plate mazda 6, bought it a few month ago full mazda service history aside from the service done by the garage I bought it from. Plugged it into the diagnostics machine and it is saying there is a dpf problem. I've heard that it doubles as a service light and madza reset it when they personally perform a service. So my question is if I reset my dpf light myself and there is genuinely a problem with my filter will it come back on? I don't want there to be a problem that I'm unaware of but also don't want to be paying a fortune trying to get to the bottom of this to find that it's just a service light.? Any help on this would be greatly appriciated, bearing in mind I don't know an awful lot about cars. Thanks!

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Sat 17 Jan 2015 13:04
Mazda 6 - Mazda 6 DPF light help! - Railroad.
The way modern car engines run are driven not by performance or fuel economy, but by strict emission regulations. Your Diesel engine produces particulate matter just like older diesels did. In years gone by this PM was just allowed to pass through the exhaust system and into the atmosphere, thus causing pollution. Eventually it was discovered that this pollution was causing major problems. Modern diesels are just as polluting at source, but the difference between them and older cars is that pollution control today is managed. This is why your car has a Diesel Particulate Filter.

Particulate matter is collected inside the DPF whilst the car engine is cold, and when driving conditions are such that allowing the PM to escape would cause pollution ie. driving in urban areas. When you are on a motorway driving at a steady speed the Engine Control Module will add extra fuel to be burned inside the exhaust system. This purpose is to raise the temperature of the exhaust system and burn off the PM that has collected inside the DPF and reducing it into smaller particles that can then pass through the filter. This is known as the 'Regeneration' process. Not all PM can be burned off, and so eventually the DPF will become so blocked that not even a regeneration can clear it. The more short journeys you do in your car the sooner a new DPF will be required.

I won't go into all the whys and wherefores, but I hope I have given you a bit in an insight. If you want to know more please post back.
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Sat 17 Jan 2015 17:31
Mazda 6 - Mazda 6 DPF light help! - craig-pd130

In your case, I believe it is likely that the DPF light is indicating the DPF is nearly full. Read the DPF section in your owner's manual carefully, and follow the instructions.

Also read the section in your owner's manual about the oil level, then check the oil level EXACTLY as it says in the manual. If the oil level is too high then the car needs urgent attention.

Unfortunately, Mazda diesels similar to yours do seem to have problems with the DPF system.

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