SsangYong Rodius (2013 year). Manual - part 82

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2) Collecting PM of DPF

There is a filter installed in the DPF and the PM filtered by this filter is burned (regeneration) when the 

temperature of exhaust gas is increased due to post-injection. The filter has a honeycomb-like 

structure to capture the particulate matter and the inlet and outlet of each channel are closed 

alternatively. Once the exhaust gas enters to the inlet of a channel, it is released from the outlet of the 

adjacent channel through the porous wall because of the closed outlet of the first channel, and the PM 

is collected in the first channel.

[Collecting PM of CDPF]

Normally, when the driving distance becomes approx. 600 to 1,200 km, enough amount of soot to 

be burned is filtered and accumulated in the CDPF. The ECU increases the amount of fuel post-
injection to increase the temperature of the exhaust gas up to 600°C, so that the soot is 

burned. The soot is burned for 15 to 20 minutes (may differ by conditions).

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3) PM Regeneration of DPF

The differential pressure sensor installed in the DPF measures the pressure values of inlet and outlet of 

CDPF. And the amount of the PM collected in the filter is calculated based on the exhaust temperature, 

intake air mass flow, booster pressure, etc. 

The regeneration is started when the amount of the collected PM is 28 g or more. 
The ECU commands post-injection to increase the temperature of CDPF to 600℃.

When the amount of the collected PM is not enough: The DPF works as a filter. 

1.

When enough amount of PM is collected: The ECU commands post-injection and increase the 

exhaust gas temperature to start regeneration.

2.

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4) Fuel Injection During CDPF Regeneration

The injection method in D20DTR engine has three steps;

Pilot injection, Main injection, Post injection

Post injection

 ▶

The post injection is the injection process after main injection and consists of ‘After injection”, 
“Post 1 injection” and “Post 2 injection”. All of post injections are to reduce the PM and 

harmful exhaust gas. The post injection does not make the actual output. The post injection activates 

the fuel by injecting the fuel to the incompletely combusted gas after primary combustion. Through the 

process, the PM and smoke in the exhaust gas could be reduced. There are totally 7 injections as 

shown in the figure. However, all of 7 injections are not performed during driving because it decreases 

the fuel economy. Totally 5 injections can be performed in one cycle.

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6. CIRCUIT DIAGRAM