摘要 |
Method and apparatus for operating an exhaust-gas catalytic converter (21) of an internal combustion engine having at least one cylinder (Z1-Z4) and one exhaust-gas section (4), in which the exhaust-gas catalytic converter (21) and a lambda probe (43) downstream of the exhaust-gas catalytic converter (21) are arranged. A characteristic value which is representative for the NOx concentration is determined as a function of a measured signal (VLS DOWN) of the lambda probe (43). |