摘要 |
A NOx trap is associated with oxidation catalyst-forming structure integrated in a common medium, and is located in an exhaust line of a motor vehicle diesel engine. The engine can be controlled at least with a rich mixture control strategy and with lean mixture control strategies of level 1 and level 2. The system acquires the temperatures upstream and downstream torn the trap, and on detecting a request to purge sulfate, it compares the temperatures with first and second curves for controlling operation of the engine with a rich mixture if the temperatures lie between said curve, and otherwise with a lean mixture. The system also compares the temperatures with third and fourth curves for controlling operation of the engine to apply the level 2 strategy if the temperatures lie between said curves, Or otherwise to apply the level 1 strategy.
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