Mazda 6 Facelift 2005, Training Manual

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Diesel Engines Engine
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The channels of the DPF are coated with platinum. This catalytic coating facilitates the
regeneration of the filter by significantly lowering the light-off temperature of the soot and
by accelerating the combustion of the particles. Without coating the burn-off of the
particles takes place above a temperature of approx. 600 °C. Due to the effect of the
platinum coating the light-off temperature of the soot is lowered to 500 °C.
•
After regeneration ash residues that have formed from the engine oil and diesel fuel
remain in the DPF and cannot be further converted. These residues reduce the usable
filter volume, shortening the regeneration intervals. Since the filter pores are clogged by
the ash residues, the exhaust gas back-pressure and hence the fuel consumption are
increased. Due to the use of engine oil with low ash formation, these effects can be
reduced to a minimum. For this reason, there is no replacement interval given for the
filter.
•
However, depending on the operating conditions the usable filter volume may reach the
limit within the lifetime of the vehicle. In this case, the DPF must be replaced.
NOTE: After replacing the DPF, several steps must be performed to ensure its proper
function (refer to the section “Control System, Service and Repair”).
M5_01039
X Exhaust-gas volume flow Y Differential pressure
1 Used filter 3 Differential pressure limit
2 New filter
01-62 Service Training Mazda6 Facelift