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NOx catalyst efficiency below threshold
Absorbs and stores NOx gases to reduce emissions.
Costs
Every car issue can be caused by different things. Here are the most common ones
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Most Expensive
Most Expensive
Moderate costs
Cheapest case
Discussions
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Details
Probability
Based on the values and symptoms you have entered, a crude estimation of the probability of this problem can be made
HIGH
Typical consequences
If this defect is detected, it may lead to the following problems:
- Exhaust system damage
- Failure of the exhaust emission test (Failure to pass the exhaust emission test)
Function of the NOx catalyst
The NOx storage catalytic converter removes the nitrogen oxides from the exhaust gas. It stores them until its absorption capacity is reached. After regeneration, the NOx storage catalyst repeats its work. The storage catalytic converter can only store NOx in a temperature range of 150 to 500° C.
During a cold start, the engine has not yet reached the desired temperatures. Therefore, a cold start is critical. During normal driving (300 to 400° C operating temperature), it instead reaches its maximum efficiency of around 80 percent. The vehicle has an additional consumption of approx. 2 percent during regeneration of the NOx storage catalytic converter.